Final answer:
The nurse should explain that the cervical cap can be used for repeated acts of intercourse without the need for additional spermicide, making it more convenient compared to a diaphragm for multiple acts of intercourse.
Step-by-step explanation:
A client asks about the major differences between the cervical cap and the diaphragm as contraceptive methods. Both are barrier methods of contraception, but there are key differences between them. The most accurate response from the nurse would be: "D. 'The cervical cap can be safely used for repeated acts of intercourse without adding more spermicide later.'" Unlike the diaphragm, which should be supplemented with additional spermicide with each act of intercourse, the cervical cap does not require additional applications of spermicide after being placed. It is designed to remain effective for repeated intercourse once it has been positioned correctly and spermicide has been applied. Additionally, while diaphragms must be left in place for at least six hours after intercourse, the precise duration for which a cervical cap can be left in place can vary, but often it can be worn for a longer period of time compared to a diaphragm.