Achilles knows the flaw in the minor that hector is wearing and stirkes him there where does he strike him
a. at the gullet
b. on the heel
c. on his wrist
d. at his heart

The other answer is incorrect, but only because your question is formulated in a weird and incorrect way. 
So, you are asking us here where did Achilles strike Hector, and the answer is A. at the gullet. That is the only flaw in Hector's armor that is unprotected - around the throat area. If, however, you want to know where Achilles was hurt, then yes, the answer would be on the heel, as it is his only weak spot.