The correct answer here is Option C) - 'Had already left'. This is because this phrase satisfies the rules of proper grammatical convention the best and follows the tense of the sentence as well (in this case, primarily past perfect). The answer is had already left as the past perfect is used to refer to an action that has finished before another action in the past; in this case when Girijia arrived, Usha had already left. All other options are incorrect.