Which Explanation Best Describes Why Earth Observers Always See the Same

Which explanation best describes why Earth observers always see the same face of the moon?

A) The Moon's rate of spin matches the rate at which the Moon revolves around Earth.
B) The Moon does not rotate as it circles Earth.
C) We tend only to observe the Moon at night, not during the day, when the opposite face is facing toward Earth.
D) Earth and Moon are partially gravity locked.