Explanation

The system that controls hand movements for playing the piano is the nervous system.

The nervous system, particularly the brain and the peripheral nerves, controls and coordinates muscle movements

Additional information:

Skeleton:

Provides structure and support to the body

Circulatory:

Transports blood, nutrients, oxygen, carbon dioxide, and hormones throughout the body

Immunity:

Defends the body against infections and diseases by identifying and neutralizing pathogens