Answer:
The correct answer is letter "D": voluntary.
Explanation:
Voluntary turnover refers to the situation in which employees quit their jobs because of several reasons: inadequate work conditions, low wages, or better job opportunities are some of them. In some other cases, the lack of opportunities to follow a path career pushes employees to look for different companies where to work.
Therefore, the software firm of the example is looking for the voluntary turnover of its designers to avoid the process of firing them.