A client, now 37 weeks pregnant, calls the clinic because she’s concerned about being short of breath and is unable to sleep unless she places three pillows under her head. After listening to her concerns, the nurse should take which action（）

A. Make an appointment because the client needs to be evaluated.

B. Explain that these are expected problems for the latter stages of pregnancy.

C. Arrange for the client to be admitted to the birth center for delivery.

D. Tell the client to go to the hospital; she may be experiencing signs of heart failure from a 45% to 50% increase in blood volume.

具有双受精现象的植物类群是（　　）

A．高等植物

B．藻类植物

C．被子植物

D．种子植物