Question

genetic characteristics that we cant control include ________.
a. height and amount of muscle fibers
b. amount of muscle fibers and heart rate
c. heart rate and flexibility
d. flexibility and amount of daily exercise

please select the best answer from the choices provided.

○ a
○ b
○ c
○ d

Explanation:

Height is heavily determined by genetics, and the number of muscle fibers a person has is set at birth (genetically determined) and cannot be changed. Heart rate can be modified through training, flexibility can be improved with stretching, and daily exercise is a voluntary, controllable behavior.

Answer:

A. height and amount of muscle fibers