Which detail from the story explains why Martha expects to receive the scholarship jacket?

A. I had been a straight A student since the first grade
B. I decided I wasn't going to make it any easier for him
C. I couldn't wait to tell Grandpa and ran straight to the field
D. I skipped and ran back to the house whistling some silly tune

A. I had been a straight A student since the first grade

The detail from the story that explains why Martha expects to receive the scholarship jacket is option A: "I had been a straight A student since the first grade."

To find the detail from the story that explains why Martha expects to receive the scholarship jacket, we need to analyze the options given and select the one that directly relates to Martha's expectation.

A. "I had been a straight A student since the first grade" - This option suggests that Martha's academic performance is excellent, but it does not explicitly explain why she expects to receive the scholarship jacket.

B. "I decided I wasn't going to make it any easier for him" - This option indicates Martha's determination to not make things easier for someone, but it does not directly explain why she expects to receive the scholarship jacket.

C. "I couldn't wait to tell Grandpa and ran straight to the field" - This option shows Martha's excitement to share the news with her grandpa, but it does not explicitly explain her expectation of receiving the scholarship jacket.

D. "I skipped and ran back to the house whistling some silly tune" - This option does not provide any information related to Martha's expectation of receiving the scholarship jacket.

Based on the given options, none of them explicitly explain why Martha expects to receive the scholarship jacket. It is possible that the answer may not be explicitly stated in the story or that additional context is needed to make an accurate inference.