The rigid zones on the surface that form drifting tectonic plates are called lithospheric plates.

Here's why:

* Lithosphere: This is the rigid outermost layer of Earth, composed of the crust and the uppermost part of the mantle.

* Asthenosphere: This is a partially molten layer beneath the lithosphere. The lithospheric plates "float" on the asthenosphere.

* Plate Tectonics: The theory of plate tectonics explains that the lithosphere is broken into large plates that move slowly over the asthenosphere. These movements cause earthquakes, volcanic activity, mountain formation, and other geological phenomena.

So, to be more specific, the answer is lithospheric plates, which are composed of the crust and the uppermost part of the mantle.