According to the definition of regression testing, it is a type of software testing that confirms that a recent program or code change has not adversely affected existing features1 It involves re-running functional and non-functional tests to ensure that previously developed and tested software still performs as expected after a change2 If the software does not perform as expected, it is called a regression. Therefore, the most important goal of regression testing is to ensure new releases do not impact previous stable features.
The other options are not correct because:
* Option A is not correct because the expected outputs are provided by the new features is not the goal of regression testing, but rather the goal of functional testing or acceptance testing. These types of testing aim to verify that the software meets the specified requirements and satisfies the user needs. Regression testing, on the other hand, focuses on checking that the existing features are not broken by the new features3
* Option B is not correct because the system can handle a high number of users is not the goal of regression testing, but rather the goal of performance testing or load testing. These types of testing aim to evaluate the behavior and responsiveness of the software under various workloads and conditions. Regression testing, on the other hand, focuses on checking that the software functionality and quality are not degraded by code changes4
* Option C is not correct because the system can be restored after a technical issue is not the goal of regression testing, but rather the goal of recovery testing or disaster recovery testing. These types of testing aim to assess the ability of the software to recover from failures or disasters and resume normal operations. Regression testing, on the other hand, focuses on checking that the software does not introduce new failures or defects due to code changes5 References: 1: Wikipedia. Regression testing - Wikipedia. [Online]. Available: 3. [Accessed: 14-Apr-
2023]. 2: Katalon. What is Regression Testing? Definition, Tools, Examples - Katalon.
[Online]. Available: 4. [Accessed: 14-Apr-2023]. 3: Guru99. What is Functional Testing? Types & Examples
- Guru99. [Online]. Available: . [Accessed: 14-Apr-2023]. 4: Guru99. What is Performance Testing? Types & Examples - Guru99. [Online]. Available: . [Accessed: 14-Apr-2023]. 5: Guru99. What is Recovery Testing?
with Example - Guru99. [Online]. Available: . [Accessed: 14-Apr-2023].

Explanation
Dynamic application security testing (DAST) is a method of testing the security of an application by simulating attacks from an external source. DAST does not require access to the source code or binaries of the application, unlike static application security testing (SAST), which analyzes the code for vulnerabilities.
Therefore, DAST is a black box testing technique, meaning that it does not need any knowledge of the internal structure, design, or implementation of the application. DAST is also programming language agnostic, meaning that it can test applications written in any language, framework, or platform. This makes DAST more flexible and adaptable to different types of applications and environments. However, DAST also has some limitations, such as being slower, less accurate, and more dependent on the availability and configuration of the application. References:
SAST vs. DAST: What's the Difference?
SAST vs DAST: What's the Difference?
SAST vs. DAST: Enhancing application security