Question

plate tectonics: divergent boundaries
on which layer of the earth will the tectonic plates be found?
the lithosphere
the lower mantle
the inner core

Explanation:

Tectonic plates are part of the Earth's rigid outer shell, the lithosphere. The lithosphere includes the crust and the uppermost part of the mantle and is broken into these plates which move relative to each other. The lower mantle and inner - core are deeper layers not where tectonic plates are located.

Answer:

A. the lithosphere