Available choices:
A). loose soil
B). Rocks breaking down
C). salt and water.
D). The area was once underwater
E). A lot of rain
F). Dry air
G). Hot temperatures
H). tectonic plates coliding
Given those answer options, answer the question: You are presented with the quiz "Where does silt come from?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "weathering means breaking down rocks from larger whole into smaller pieces by weather" and "silt forms form the weathering of rocks". So, what's the best answer to the question?
A:
B).