PMP,Tell me the answer and why

PMP,Tell me the answer and why
One of your employees is up for promotion.If the promotion is granted,the employee will be reassigned elsewhere causing a problem for you on your project.You can delay the promotion until your project is complete.You should:
A.Support the promotion but work with the employee and the employee's new management to
develop a good transition plan
B.Ask the employee to refuse the promotion until your project is completed
C.Arrange to delay the promotion until the project is completed
D.Tell the employee that it is his responsibility to find a suitable replacement so that the project will
not suffer