He went there, _____ some books and call on an old friend of his.
A. bought B. buying C. buy D. to buy
He went there, _____ some books and call on an old friend of his.
A. bought B. buying C. buy D. to buy
D
and call on暗示与前面的形式必须一致。而He went there暗示去的目的，所以用不定式作目的状语，与（to）call on并列。