A.) A question that causes a larger debate or conversation.
Explanation:
A research question is one that cements a research plan whose methodology needs to be clearly addressed and whose results —following the ethical guidelines of academia and research in general— can be potentially grasped but, from the start, are still unknown. These characteristics make an effective research question begin a dialogue, a debate of a broad nature that can advance the state of the art of the topic selected in the question.
This is an example of a simile, a comparison between two things using the words "like" or "as." "Gloomy as the night" is the simile here, since his sadness is being compared to nighttime.
