Which of the following is not a function of the crebellum?
a. voluntary muscle coordination
b. regulates heartbeat
c. maintain muscle tone
d. maintain balance when standing

b. regulates heartbeat

Explanation:

The cerebellum is responsible for reflexes and voluntary movements, it also acts on the muscular system being responsible for muscle tone.

In general, it can be understood that the cerebellum is the region of the brain that captures the sensory impulses of joints, tendons, muscles, as well as balance and visual receptors.

The cerebellum is a part of the central nervous system that is mainly related to our posture and balance. It occupies a large part of the posterior cranial fossa and constitutes approximately 10% of the brain volume. It is located dorsally to the bulb and the bridge and is connected to the medulla and the bulb by the cerebellar peduncle.

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.