I uploaded the answer to a file hosting. Here's link:
tinyurl.com/wtjfavyw
that is known as : Volunteer Reinforcement
Since the house has a very limited man power to do some tasks that is very important for the Government, they often ask for Public's help to do it for them ( usually those who support the current Government officials)
A, B, and C are true so that would leave D as your answer.
This is called monogamy as opposite to polygamy (multiple spouses at the same time).
