Muscles directly cause
a. the release of hormones.
b. the regeneration of nerves.
c. the extension of limbs.
d. the healing of wounds.

The answer is letter C.  

Muscles directly cause the movement of limbs in the body. These are mostly made up of striated tissues that slide along each other causing the movement of the whole body. These tissues are attached to the bones that make up the skeletal system. They provide the structure and frame of the body and they also serve as cushions and protection for the bones. Without muscles movement will not be possible and we would seem like hollow structures only made up of bones.

35 cubic feet of dirt if it's digging a burrow

Adescription of  congestive heart  failure, its symptoms, risk factors, and treatment. to the  heart muscle  other than by artery or blood  flow  problems; signs of  heart  failure may not  meanthe patient has  heart  failure and they quit alcohol, or at least consume alcohol within the national recommended  limits.