English Grammar Error Identification

Directions Given below are three sentences. One, two or all the sentences may have error(s) of grammar or syntax or Standard English usage. Identify only the sentences that are incorrect.(A) The conjuror had ready wit, indulged in incoherent mumbo jumbo and performed tricks that caught immediate fancy of the children.
(B) Not having received any reply to his question, the teacher realized that the students had not followed what they had been taught.
(C) She is as good if not better than the best student in the class.