The phrase <em>the antique fire truck </em>is used as a complete subject, because you are including all of these words to form a subject, so it cannot be a simple one (just one word). It isn't a compound subject either, because that would be two or more words connected with a conjunction <em>and, </em>or some other one.
The correct answer is:
B) <em>the concept that a high rate of consumption and spending are the basis for a sound economy</em>
B. Is correct. "Neither the umbrellas nor the tree protects us from the sun."
Hope this helps! Have a great day :)
