The nurse is caring for a woman with phenylketonuria who wants to start a family. Which of the following guidelines should the nurse provide the woman

A. Follow a low-phenylalanine diet before trying to conceive.
B. A low-phenylalanine diet is necessary only during the first trimester.
C. Begin a low-phenylalanine diet when pregnancy is confirmed.
D. Dietary restrictions won’t be necessary.

以下带电作业方法为直接作业法的是（）。

A.地电位作业

B.等电位作业

C.中间电位

D.带电冲洗