Which statement best reflects what is known about the theory of plate tectonics?

a .earth's lithosphere is composed of about five large plates and a few smaller plates that move across earth's surface a few meters a year.

b. earth's lithosphere is composed of dozens of plates that move across earth's surface a few kilometers a year.

c. earth's lithosphere is composed of hundreds of plates that move across earth's surface a few centimeters a year.

d. earth's lithosphere is composed of about a dozen large plates and a few smaller plates that move across earth's surface a few centimeters a year.