Answer:
D
Explanation:
There are only 2 ways to explain this.
distance
and brightness caused by what it is burning.
A is true but it is not the explanation of why it is true.
B this is actually not true. Other stars would burn much more.
C It is not the largest star. In fact it is in the lower middle.
D is the answer. 93 million miles as these things go, is not every much.
