Which practice is described by adding lines of code after testing and commenting on them?

• A. They add lines of code and comment on them after testing
• B. They remove all new lines after testing
• C. They only adjust the styling of the code
• D. They publish immediately without review

Answer: (A)

Documenting changes after testing and commenting on the new code focuses on making the purpose and rationale of updates clear. When testing reveals issues or opportunities, adding the new lines of code to implement a fix or enhancement is only part of the work. Pairing that code with comments that explain why this particular approach was chosen, what the code is supposed to do, and any caveats or assumptions helps others understand the change without tracing through the entire history. This practice supports maintainability, easier reviews, and quicker future debugging because the intent behind the modification is visible at the point of the change. The other behaviors described—removing the new lines, only touching styling, or publishing without review—do not capture the ongoing need to document what was added and why, which is essential for a healthy codebase.