问题详情

A．He can return the books and get the full refund for the first three weeks of the class.
B．He can return the books and get a part of the refund at any time.
C．He can change the books for his favorite ones at the book store.
D．He can write his name in the text or mark it up before he returns the books.请帮忙给出正确答案和分析，谢谢！