Question

with age, muscles can become weaker. this is due to
a. connections between nerves, which cause more pain and therefore less use
b. damage from everyday use and injuries that accumulate over time
c. disconnections between motor nerves and muscle fibers
d. difficulties that occur during muscle growth and repair

please select the best answer from the choices provided.

a
b
c
d

Explanation:

To determine the correct answer, we analyze each option:

• Option A: Nerve connections causing pain and discomfort isn't the primary reason for age - related muscle weakness. Muscle weakness with age is more about structural and functional changes in muscles and their neural connections related to disconnection, not just pain - related nerve issues.
• Option B: While everyday use and injuries can contribute to muscle problems, the cumulative damage from these is not the main reason for the general muscle weakness associated with aging. Aging - related muscle weakness has more to do with the loss of connection between motor nerves and muscle fibers.
• Option C: As we age, there is a disconnection (or loss of innervation) between motor neurons (nerves) and muscle fibers. This loss of proper neural control over muscle fibers leads to muscle weakness. This is a well - known physiological change associated with aging and muscle function.
• Option D: Muscle growth and repair difficulties are not the main cause of age - related muscle weakness. The primary issue is the disruption of the connection between motor nerves and muscle fibers, not problems during the growth and repair process itself.

Answer:

C. disconnections between motor nerves and muscle fibers