20 points!!!

Read the sentence from paragraph 12.

And let's not forget—forests are an indispensable source of green energy and green building materials.

How does this sentence refine an important point that Christiansen makes in this passage?

A.
by sharing that the forests are in danger of disappearing if people rely on them too much for energy
B.
by emphasizing that the country needs to invest more in green energy and green building materials
C.
by explaining that forests are needed for survival, so everyone needs to help preserve them
D.
by reminding the reader that everyone benefits from forests, not just people who own forest land