In ServiceNow, Application Files are configuration records that define the various components and logic that constitute an application. These include artifacts such as:
Business Rules
Client Scripts
UI Actions
Script Includes
Tables and Fields
Workflows
These artifacts collectively define the functionality and behavior of the application. When an application is developed, ServiceNow automatically creates and manages these Application Files to represent the application's components.
Option C is correct because Application Files are the fundamental building blocks that comprise a ServiceNow application, representing its various components and configurations.
Options A, B, and D are incorrect:
A: XML exports of an Update Set represent changes made to an instance but are not synonymous with Application Files.
B: CSV files are typically used for data import/export and do not represent the configuration components of an application.
D: An XML export of table records pertains to data within a table, not the configuration artifacts that define application behavior.

User-defined non-inherited fields can be deleted from a table in ServiceNow. These are fields that are created by users on a specific table and are not inherited from a parent table. Inherited fields cannot be deleted from a table, as they are defined on a parent table and shared by all child tables. Any field on a table cannot be deleted, as some fields are system-defined and essential for the table functionality. Table records are not deleted when a field is deleted, as the field deletion only affects the table structure and not the data. Reference: Delete fields

A transform map determines the relationships between fields displaying in an Import Set table and fields in an existing ServiceNow table, such as the Incidents or Users table.
Reference:
The following platform feature can be used to determine the relationships between fields in an Import Set table to fields in an existing ServiceNow table:
Transform Map. This is a feature that defines the mapping between the fields of an Import Set table and the fields of a target table, such as incident, problem, or user. A transform map also specifies the logic and rules for transforming the imported data, such as coalescing, scripting, or applying data policies.
The following platform features are not used to determine the relationships between fields in an Import Set table to fields in an existing ServiceNow table:
Business Service Management Map. This is a feature that provides a graphical representation of the configuration items (CIs) and their relationships in the Configuration Management Database (CMDB). A Business Service Management Map can be used to visualize the impact of incidents, changes, or problems on the CIs and the services they support.
Data Sources. This is a feature that defines the connection and authentication information for an external data source, such as a file, a JDBC database, or a web service. A data source is used to import data from the external source into an Import Set table.
CI Relationship Builder. This is a feature that creates relationships between CIs in the CMDB based on predefined or custom rules. A CI Relationship Builder can be used to populate the CMDB with the dependencies and connections between the CIs. References: Transform Maps, Business Service Management Map, Data Sources, CI Relationship Builder