How can the satellites catch the information about the soil

A．By turning the intensity of sunshine into maps.

B．By analyzing the recent weather report.

C．By capturing the microwave radiation from the soil.

D．By analyzing information provided by ground observation centers.

国产天然气氨压缩浅冷装置制冷系统正常停车时，关闭氨蒸发器供液阀，使蒸发器氨压力（）。

A.增大

B.减小

C.不变

D.归零