Among the objects found in the excavated temple were small terra-cotta effigies left by supplicants who were either asking the goddess Bona Dea’s aid in healing physical and mental ills or thanking her for such help.

(A) in healing physical and mental ills or thanking her for such help
(B) in healing physical and mental ills and to thank her for helping
(C) in healing physical and mental ills, and thanking her for helping
(D) to heal physical and mental ills or to thanks get for such help
(E) to heal physical and mental ills or thanking her for such help

The correct answer is (A) and I understand that it is the best choice because the construction is parallel with the correlative conjunction either/or (either asking… or thanking)

My question – both (A) and (E) follow the parallel construction around either/or. But OG explanation says in (E) ‘to heal’ after aid is incorrect.

Could someone explain why?

Thanks

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