What triggers/initiates muscle relaxation?

a. action potential is generated on sarcolemma
b. atp binds to the myosin head
c. release of calcium from the sarcoplasmic reticulum
d. removal of acetylcholine from the neuromuscular junction
e. acetylcholine is released into the neuromuscular junction and an action potential is generated on the sarcolemma.

c. release of calcium from the sarcoplasmic reticulum