16. Renewable energy sources, such as solar and wind power, __________ as sustainable alternatives to fossil
fuels.
(A) have been promoted
(B) has been promoted
(C) being promoted
(D) promoted
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統計: A(202), B(12), C(12), D(18), E(0) #3223536
統計: A(202), B(12), C(12), D(18), E(0) #3223536