A reliable source is a document!
B, D, and E are the correct answers. Literary themes are usually profound statements that teach a "lesson". A and C are just random sentences that don't have meaning.
I think it was named the bald eagle because of the contrast in colors. The body is brown and the head is white, like you said, so when it is flying it looks bald because the head is lighter. I think that might be the reason
B. Traverse
Normally, a speaker would use the word "move" as in "move forward" instead of "traverse forward"
