C. They study true movement of earthquake waves
The answer to your statement is TRUE!!
I would say either the first, second, or fourth answer; waves have a very strong impact on the movement of sand and other particles under the water. Erosion of particles off an island are similar in this case.
It wouldn't be anything about a tropical storm; it's no where in the question and we don't know how many storms Florida has or how strong they are.
I would think that it is B or C
Using a bike instead of a car