I say it would be an online encyclopedia about seahorses would be the most helpful. While an atlas of the Atlantic Ocean might help it doesn't focus on the one topic as well as the web page about animals. Then, a poster doesn't seem to give much information making C. look like your best answer. I hope this helps!
The passage above is an excerpt from this. If the underlined word, which is "crisis", be substituted with the word "event" instead, this would create a tone of less intense. Answer is opt
