Question

select the correct answer. along with earths crust, which portion of the upper mantle forms the lithosphere? a. cooler, more rigid outer portion b. hotter, liquid - like inner portion c. cooler, liquid - like inner portion d. hotter, more rigid outer portion

Explanation:

The lithosphere is composed of the Earth's crust and the cooler, more rigid outer portion of the upper mantle. This rigid layer contrasts with the asthenosphere (hotter, more fluid - like part of the upper mantle). Option B refers to a hotter, liquid - like inner portion which is part of the asthenosphere. Option C has a cooler liquid - like inner portion which is incorrect as the cooler part is rigid. Option D has a hotter rigid outer portion which is wrong as the rigid outer portion is cooler.

Answer:

A. cooler, more rigid outer portion