In a convection cycle, what causes plastic-like material to sink? a. it loses heat to the crust. b. it gains heat from the crust. c. it loses heat to the outer core. d. it gains heat from the outer core.

In a convection cycle, plastic-like material sinks when: It loses heat to the crust.

https://en.wikipedia.org/wiki/Mantle_convection

Explanation:

https://en.wikipedia.org/wiki/Mantle_convection  here is ur proof that  A is right

your answer is 20. hope this !