Rigor Mortis Upon Death Is Due to

Rigor mortis upon death is due to

A) depleted calcium availability, so actin is "frozen" away from myosin
B) calcium released from the sarcoplasmic reticulum floods the cell, causing a massive contraction event
C) actin polymers break down quickly with cell death, "freezing" the cell in place
D) depleted ATP keeps the ADP-myosin-actin complex "frozen" in its contractile state
E) depleted ATP keeps the myosin from interacting with actin, "freezing" the cell in place