A disorder in which hard fibrous tissue replaces myelin, impeding neural transmission is called _______.

A) Parkinson's disease
B) Multiple sclerosis
C) Alzheimer's disease
D) Phenylketonuria

Multiple Sclerosis

A disorder in which hard fibrous tissue replaces myelin, impeding neural transmission.

Neural Transmission

The process by which nerve cells (neurons) communicate with each other through electrical and chemical signals across synapses.

Parkinson's Disease

A progressive neurological disorder characterized by movement difficulties, such as tremors, stiffness, and bradykinesia, as well as non-motor symptoms.