From the given sentence, form a feminine noun from the masculine one:
It was his brother who took the initiative to break the cursed vase.The answer to the given sentence would be Option C, Sister.
As per the question, the sentence would have the male gender noun to be replaced by the feminine noun. The only male gender noun in the given sentence is the word ‘brother’, which means the male sibling. The exact word which happens to be the opposite to the given noun is Option C, Sister. The other options A, Father is a male gender noun and hence is the wrong answer, while option B, Mother and option D, Aunt, are both female counterparts of Father and Uncle respectively, and are hence the wrong answers.
Thus, Option C, Sister is the correct answer.