Are you referring to this question?
The fact that Mercury has no atmosphere is evidence that it
a. reflects almost all of the sunlight that strikes it.
b. is composed almost entirely of gases.
c. is much farther from the sun than it appears.
d. reflects a small percentage of the sunlight that strikes it.
If so, the answer is letter d.
The fact that Mercury has no atmosphere is evidence that it reflects a small percentage of the sunlight that strikes it.