To answer this question, we need to understand the concept of regression testing. Regression testing is a type of software testing that is performed to ensure that previously developed and tested software still performs correctly after changes or additions have been made. It helps identify any defects or issues that may have been introduced due to these changes.
Let's go through each option to understand why it is correct or incorrect:
Option v) every week - This option is incorrect because regression testing should not be performed every week. The frequency of regression testing should be determined based on the software changes and other factors.
Option w) after the software has changed - This option is correct because regression testing should be performed after the software has changed. It helps ensure that the existing functionality has not been affected by the changes.
Option x) as often as possible - This option is incorrect because regression testing should not be performed as often as possible. The frequency of regression testing should be determined based on the software changes and other factors.
Option y) when the environment has changed - This option is correct because regression testing should be performed when the environment has changed. Changes in the environment can impact the functioning of the software, and regression testing helps identify any issues caused by these changes.
Option z) when the project manager says - This option is incorrect because regression testing should not be performed solely based on the project manager's decision. The decision to perform regression testing should be based on factors such as software changes and environmental changes.
Based on the explanations above, we can see that options w and y are true, while options v, x, and z are false.
Therefore, the correct answer is option C) w & y are true, v, x & z are false.