In the context of skeletal muscles; which statement regarding DHP, RYR and Calcium-activated-Calcium channels is true?

Group of answer choices

a. All three channels return calcium to the sarcoplasmic reticulum at rest
b. All statements are true
c. All three channels contribute to the surge in intracellular calcium.
d. Only the RYR channels allow calcium to exit the sarcoplasmic reticulum.
e. Only the DHP and RYR channels contribute to the surge of calcium in the muscle cell