Sentence Correction (SC) | Re: Because her mother was unable to support a family, Marilyn Monroe spen

I checked A.

Sentence means

Because her mother was unable to support a family :- sen begins with providing a reason,
MM spent first.....................with a couple :- correct

issue is analyzing the relative pronoun clause. :who....

couple who became foster parents to supplement ( in order to supplement ) their income.
C states that couple became foster parents in order to supplement Marlyns income. it not only changes meaning, infact add another parameter to sentence which was not stated
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