C, Restate the question as a statement, its a writing strategy so none of the other ones would make sense.
The correct answer is cause/effect.
Cause and effect is the principle of causality establishing <em>one event or action</em> <em>as the direct result of another</em>.
One event causes another to happen. A cause creates an effect.
Because I went to Washington (cause) and I visited many monuments and museums, I now have new insight into the history of the United States (effect).
The insight I have now (effect) happened because I went to Washington (cause).
