问题
In modern society, alternative energies __________traditional ones are playing an important role in our daily life. That’s justbecause scientists have made great breakthroughs _________ the development ofscience and technology.
A:are notobserved
B:of, during
C:by, in
D:to, in
B:of, during
C:by, in
D:to, in
正确答案是：
