Correct answer: BA is incorrect as the past participle of 'lesen' is gelesen, not gelest. Correct version: Er hat ein Buch gelesen.C is incorrect because when you use form the perfect tense with 'gehen', the auxiliary verb used is 'sein' not 'haben' as gehen implies movement and therefore 'sein' is used. Correct version: Wir sind in die Schule gegangen.B is correct as 'fahren' uses the auxiliary verb of 'sein' when forming the perfect tense, as fahren implies movement.