【单选题】Read a text about 'Wind Power in the US' and answer some questions.Wind Power in the USPrompted by the oil crises of the 1970s, a wind-power industry flourished briefly in the United States. But then ...
A.
Cost was a big factor in preventing the development of wind power
B.
Wind power can provide enough electricty for the United States
C.
Some US states are powered solely by wind
D.
Wind power has developed steadily since the 1970s.