Read the following poem, then answer the question that follows: Reginald wanted perfect grades,
and it almost worked out that way.
Math class was his Achilles' heel,
and he could never earn an A.

This poem makes a mythological allusion to the Greek Hero, Achilles. An Achilles' heel refers to

a difficult subject

a favorite thing

a single weakness

a surprising event

a difficult subject

Explanation:

math is his weakness

Explanation:

This poem makes a mythological allusion to the Greek Hero, Achilles. An Achilles' heel refers to a single weakness. | the poem was Reginald wanted perfect grades, and it almost worked out that way. Math class was his Achilles' heel, and he could never earn an A. It is showing a single weakness. think of the part that says "Reginald wanted perfect grades," the WANTED perfect grades, then at the end it says "he could never earn an A." meaning that, that was his weakness, he could never earn an A.

i may be wrong but i think your answer is flashback