An adverb clause is a dependent clause which cannot exist on its own, it has to be a part of the main, independent clause. So, having that in mind, the only dependent clause among these examples is 'when you return from California'. Therefore, the correct answer is B.
A.Communism poses a threat to freedom and to democracy.
Because the rise Communism threat at the time.
Answer:
9/11 showed that america will retaliate against threats to their country. meaning from then on America has been in many other wars against terrorism. Like when america helped fight ISIS.
The author can use the five senses to better help you visualize what is going on.