A．They thought they were an example of successful fertility treatment.
B．Not until they reached middle age did they think of having children.
C．Not until they had the twins did they feel they had formed a family.
D．They believed that children born of older parents would be smarter.

A．Older parents are often better prepared financially.
B．Older parents can take better care of their children.
C．Older parents are usually more experienced in bringing up their children.
D．Older parents can better balance their resources against children’’s demands.