Choose A, B, C or D as the best answer.30. The author’s main argument is that __________.Single choice

a. It is not just about whether we employ clean energy, but what technologies, where and how.

b. solar and wind power are the most acceptable forms of renewable energy.

c. there needs to be more research before we invest more in renewable energy forms.

d. there is no such thing as an environmentally ‘clean’ energy source.