Explanation:

The primary benefit of automated regression testing is to verify that existing functionalities and integrations in a software system continue to work as expected after new changes, updates, or bug fixes are introduced. It focuses on detecting unintended side effects or regressions caused by modifications, ensuring the stability and reliability of the system.

Why not the other options?

A. Identifying new functionalities and features introduced during development: This is not the primary purpose of regression testing. Regression testing focuses on validating existing functionality, not identifying new features (which is typically the role of functional or feature testing).

C. Reducing manual testing efforts and streamlining the release process: While automated regression testing can reduce manual effort and improve efficiency, this is a secondary benefit. The primary goal is ensuring existing functionality remains intact.

D. All of the above, offering comprehensive validation and optimizing release efficiency: While automated regression testing may contribute to some of these aspects, the primary benefit is specifically ensuring existing functionalities work correctly (option B), not a combination of all these goals.

References:

1. Salesforce Regression Testing: Benefits and Best Practices
"Salesforce regression testing aims to verify that existing functionalities have not been broken due to any updates or code changes. It involves testing the entire system or high-risk areas to ensure that critical features and processes continue to work as expected."

2. Salesforce Regression Testing: Meaning, Benefits, and Best Practices
"Regression testing is a type of software testing that checks whether recent changes have broken existing functionality. It verifies that features that worked before still behave as expected after code updates, bug fixes, or configuration changes."

3. Salesforce Regression Testing: Definition, Benefits, and Best Practices
"The primary goal of Salesforce regression testing is to maintain the overall integrity and stability of the Salesforce environment. By regularly performing regression tests, organizations can ensure that their Salesforce applications remain reliable and perform as expected, even after multiple updates and enhancements."

4. Understanding Regression Testing in Salesforce
"Regression testing in Salesforce ensures that existing functionality operates as designed and does not break whenever there is a configuration, update, or deployment in Salesforce."

5. Plan Testing for Salesforce New Features
"Any modifications to the codebase may inadvertently introduce regressions (that is, changes that negatively impact existing functionality). This is why our Salesforce product teams conduct rigorous regression testing to avoid this."