Question

earth is not a perfect circle. due to the ______ gravitational pull, earth bulges out on the sides closest to and farthest from the moon. this distorting pull is known as a tidal force, and it is responsible for the changes in water levels that are called high and low tides.
which choice completes the text so that it conforms to the conventions of standard english?
choose 1 answer:
a moons
b moons
c moons
d moon

Explanation:

The sentence requires a possessive form to show that the gravitational pull belongs to the Moon. The possessive of a singular noun (Moon) is formed by adding an apostrophe and an -s ('s).

• Option A: "Moons'" is the possessive form for a plural noun "Moons", but there is only one Moon, so this is incorrect.
• Option B: "Moons" is a plural noun without a possessive, which does not fit the context as we need to show ownership.
• Option C: "Moon's" is the correct possessive form for the singular noun "Moon", indicating that the gravitational pull is of the Moon.
• Option D: "Moon" is a singular noun without a possessive, which does not show the relationship of ownership required in the sentence.

Answer:

C. Moon's