Walking across a tightrope is mostly controlled by the cerebrum cerebellum brain stem bronchiole

The given blank can be filled with cerebellum.

Explanation:

The part of the brain present at the posterior end of the brain is known as the cerebellum, that is, just underneath the cerebrum. It is smaller in comparison to cerebrum. However, it is an essential component of the brain. It controls movement, balance, and coordination, that is, how the muscles work in harmony. It is because of the presence of cerebellum, one can stand straight, move around, and can keep the balance.

it would be rhyolitic hope this

a physical change is being made.