Without the in your midbrain, you could not ride a bike without giving each movement conscious thought.
a) substantia nigra
b) thalamus
c) limbic system
d) pons

a) substantia nigra

The substantia nigra also known as SN is a "basal ganglia structure located in the midbrain and is so important role in reward and movement".This area of the brain sends signals down the spinal cord in order control the muscles of the body. And is so important to have movement conscious thought.

Explanation:

a) substantia nigra

The substantia nigra also known as SN is a "basal ganglia structure located in the midbrain and is so important role in reward and movement".This area of the brain sends signals down the spinal cord in order control the muscles of the body. And is so important to have movement conscious thought.

b) thalamus

The thalamus is a large mass of gray matter located in the dorsal so then is not possible that would be on the midbrain.

c) limbic system

False the limic system is not located on the mid brain since is located on both sides of the thalamus.

d) pons

The pons "is a portion of the brain stem, located above the medulla oblongata and below the midbrain", so then is not on the midbrain and not satisfy the condition.