处方中写"二乌"是指（）

A.生何首乌、制何首乌

B.生川乌、生草乌

C.制川乌、制草乌

D.何首乌、乌药

E.乌药、制草乌

Which of the following statements is the most appropriate title for the passage

Why did the United States first launch satellites into space

A．To improve navigation for warplanes and warships.
B．To guide smart bombs that home in on moving targets.
C．To collect meteorological data.
D．To sense remote volcanic eruptions.