In the given sentence, change the underlined masculine noun to feminine:
The principal applauded the head boy for his contribution to the school. [Basic]
The answer to the given sentence is Option A, Head girl.
As per the question, the sentence would have the male gender noun to be replaced by the feminine noun, by adding a word before or after that. In the given sentence, the male noun given is ‘Head boy’, a term used for the head of the boys' section of a school or an educational institute. Thus, ‘Head girl’ would be the exact, apt opposite counterpart of the noun given, as a school requires one.
The other options, B, C and D are all ineligible terms which do not fit in as the exact opposite of the noun given in the sentence, and hence, option A, Headgirl, is the correct answer.