Explain plate tectonics theory. What will be an ideal response?

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In 1965, the ideas of continental drift and seafloor spreading were integrated into the
overriding concept of plate tectonics, primarily by the work of John Tuzo Wilson, a
geophysicist at the University of Toronto. In this theory Earth’s outer layer consists of about
a dozen separate major lithospheric plates floating on the asthenosphere. When heated from
below, the deformable asthenosphere expands, becomes less dense, and rises. It turns aside
when it reaches the lithosphere, lifting and cracking the crust to form the plate edges. The
newly forming pair of plates (one on each side of the spreading center) slide down the
swelling ridges—they diverge from the spreading center. New seabed forms in the area of
divergence. The large plates include both continental and oceanic crust. The major plates
jostle about like huge slabs of ice on a warming lake. Plate movement is slow in human
terms, averaging about 5 centimeters (2 inches) a year. The plates interact at converging,
diverging, or sideways-moving boundaries, sometimes forcing one another below the surface
or wrinkling into mountains.