Answer:
The answer is B: Scientists are confused by the different ways the rocks move, and the theories involving wind, ice, and mud have not been proven.
Explanation:
In the second paragraph, it is said that scientists have been baffled by the variety of rock movement. Then, there was a description of their movement and some possible reasons for why it happens. Some of the reasons(wind, ice and mud) were suggested by scientists. The paragraph then ends by saying that none of the theories have been confirmed by research.
This is conveyed very well by option B therefore it the correct option as the main idea of the paragraph.
