Which of the following statements about erosion is true?
a.
erosion occurs as a result of drastic changes in temperature.
b.
erosion occurs when wind or water moves over sediment, soil, or rocks.
c.
physical and chemical are the two types of erosion.
d.
movement is not required for erosion to take place.

The correct answer is B., or "Erosion occurs when wind or water moves over sediment, soil, or rocks."

the relative standard reduction potential of the half-cell in which reduction occurs; more positive than the other half-cell. reduction is a chemical process in which electrons are added to an atom or an ion; it always occurs accompanied by oxidation of the reducing agent.