Explanation
End-user computing (EUC) is a system in which users are able to create working applications besides the divided development process of design, build, test and release that is typically followed by software engineers1. Examples of EUC tools include spreadsheets, databases, low-code/no-code platforms, and generative AI applications2. EUC tools can provide flexibility, efficiency, and innovation for the users, but they also pose significant risks if not properly managed and controlled3.
The greatest risk when relying on reports generated by EUC is that the data may be inaccurate. Data accuracy refers to the extent to which the data in the reports reflect the true values of the underlying information4.
Inaccurate data can lead to erroneous decisions, misleading analysis, unreliable reporting, and compliance violations. Some of the factors that can cause data inaccuracy in EUC reports are:
Lack of rigorous testing: EUC tools may not undergo the same level of testing and validation as IT-developed applications, which can result in errors, bugs, or inconsistencies in the data processing and output3.
Lack of version and change control: EUC tools may not have a clear record of the changes made to them over time, which can create confusion, duplication, or loss of data. Users may also modify or overwrite the data without proper authorization or documentation3.
Lack of documentation and reliance on end-user who developed it: EUC tools may not have sufficient documentation to explain their purpose, functionality, assumptions, limitations, and dependencies. Users may also rely on the knowledge and expertise of the original developer, who may not be available or may not have followed best practices3.
Lack of maintenance processes: EUC tools may not have regular updates, backups, or reviews to ensure their functionality and security. Users may also neglect to delete or archive obsolete or redundant data3.
Lack of security: EUC tools may not have adequate access controls, encryption, or authentication mechanisms to protect the data from unauthorized access, modification, or disclosure. Users may also store or share the data in insecure locations or devices3.
Lack of audit trail: EUC tools may not have a traceable history of the data sources, inputs, outputs, calculations, and transformations. Users may also manipulate or falsify the data without detection or accountability3.
Overreliance on manual controls: EUC tools may depend on human intervention to input, verify, or correct the data, which can introduce errors, delays, or biases. Users may also lack the skills or training to use the EUC tools effectively and efficiently3.
The other options are not as great as data inaccuracy when relying on EUC reports. Reports may not work efficiently, reports may not be timely, and historical data may not be available are all potential risks associated with EUC tools, but they are less severe and less frequent than data inaccuracy. Moreover, these risks can be mitigated by improving the performance, scheduling, and storage of the EUC tools. However, data inaccuracy can have a pervasive and lasting impact on the quality and credibility of the reports and the decisions based on them. Therefore, option A is the correct answer.
References:
What is Data Accuracy?
What Is End User Computing (EUC) Risk?
End-user computing
End-User Computing (EUC) Risks: A Comprehensive Guide

Section: Protection of Information Assets
Explanation:
Trend/Variance Detection tool are used to look for anomalies in user or system behavior. For example, if a user typically logs in at 9:00 am, but one day suddenly access the system at 4:30 am, this may indicate a security problem that may need to be investigated.
Other types of audit trail analysis tools should also be known for your CISA exam The following were incorrect answers:
Audit Reduction tool - They are preprocessor designed to reduce the volume of audit records to facilitate manual review. Before a security review, these tool can remove many audit records known to have little security significance.
Attack-signature detection tool - They look for an attack signature, which is a specific sequence of events indicative of an unauthorized access attempt. A simple example would be repeated failed logon attempts.
Heuristic detection tool - Heuristic analysis is an expert based analysis that determines the susceptibility of a system towards particular threat/risk using various decision rules or weighing methods. MultiCriteria analysis (MCA) is one of the means of weighing. This method differs with statistical analysis, which bases itself on the available data/statistics.
Reference:
CISA review manual 2014 Page number 336
and
http://en.wikipedia.org/wiki/Heuristic_analysis

Audits should adhere to standards, guidelines, and best practices. Answer A represents a restriction on scope. B and C are components of answer D.

Section: Information System Acquisition, Development and Implementation Explanation:
Interface or integration testing is a hardware or software test that evaluates the connection of two or more components that pass information from one area to another. The objective it to take unit tested module and build an integrated structure dictated by design. The term integration testing is also referred to tests that verify and validate functioning of the application under test with other systems, where a set of data is transferred from one system to another.
For CISA exam you should know below types of testing:
Unit Testing - The testing of an individual program or module. Unit testing uses set of test cases that focus on control structure of procedural design. These tests ensure internal operation of the programs according to the specification.
Interface or integration testing - A hardware or software test that evaluates the connection of two or more components that pass information from one area to another. The objective it to take unit tested module and build an integrated structure dictated by design. The term integration testing is also referred to tests that verify and validate functioning of the application under test with other systems, where a set of data is transferred from one system to another.
System Testing - A series of tests designed to ensure that modified programs, objects, database schema, etc , which collectively constitute a new or modified system, function properly. These test procedures are often performed in a non-production test/development environment by software developers designated as a test team. The following specific analysis may be carried out during system testing.
Recovery Testing - Checking the systems ability to recover after a software or hardware failure.
Security Testing - Making sure the modified/new system includes provisions for appropriate access control and does not introduce any security holes that might compromise other systems.
Load Testing - Testing an application with large quantities of data to evaluate its performance during peak hour.
Volume testing - Studying the impact on the application by testing with an incremental volume of records to determine the maximum volume of records that application can process.
Stress Testing - Studying the impact on the application by testing with an incremental umber of concurrent users/services on the application to determine maximum number of concurrent user/service the application can process.
Performance Testing - Comparing the system performance to other equivalent systems using well defined benchmarks.
Final Acceptance Testing - It has two major parts: Quality Assurance Testing(QAT) focusing on the technical aspect of the application and User acceptance testing focusing on functional aspect of the application.
QAT focuses on documented specifications and the technology employed. It verifies that application works as documented by testing the logical design and the technology itself. It also ensures that the application meet the documented technical specifications and deliverables. QAT is performed primarily by IS department. The participation of end user is minimal and on request. QAT does not focus on functionality testing.
UAT supports the process of ensuring that the system is production ready and satisfies all documented requirements. The methods include:
Definition of test strategies and procedure.
Design of test cases and scenarios
Execution of the tests.
Utilization of the result to verify system readiness.
Acceptance criteria are defined criteria that a deliverable must meet to satisfy the predefined needs of the user. A UAT plan must be documented for the final test of the completed system. The tests are written from a user's perspective and should test the system in a manner as close to production possible.
The following were incorrect answers:
Unit Testing - The testing of an individual program or module. Unit testing uses set of test cases that focus on control structure of procedural design. These tests ensures internal operation of the programs according to the specification.
System Testing - A series of tests designed to ensure that modified programs, objects, database schema, etc , which collectively constitute a new or modified system, function properly. These test procedures are often performed in a non-production test/development environment by software developers designated as a test team.
Final Acceptance Testing - During this testing phase the defined methods of testing to apply should be incorporated into the organization's QA methodology.
Reference:
CISA review manual 2014 Page number 166