Sentence Correction (SC) | Re: Q18: According to a recent study of consumer spending on

C is the OA but i am curious why the OA has the following invalid structure : preposition + Noun + ING' construction...

Per my understanding this structure is wrong .

referring attaching MGMAT link :https://www.manhattanprep.com/gmat/forums/topic-t31623.html

please assist why is this construction okay in C