Answer:
C. the total number of people living in an area
Explanation:
The answer is the place of religion in government.
I guess the answer to the blank will be:
During the second Red Scare public and government suspicious of Communism led to the blacklisting of people in various industries.
In fact, since the Moon is constantly rotating on it's own axis, there is no area of the planetoid which is permanent darkness, and the far side of the Moon is only completely devoid of sunlight during a Full Moon - when the Sun is facing the Moon with the Earth in between.