Which statement best describes a cause and its effect that occurs during the process of muscle contraction? A.
The shortening of the sarcomere causes the release of calcium around the myofibrils.
B.
The presence of calcium ions within nerve cells causes the sarcomere to shorten.
C.
The release of calcium ions causes myosin and actin to attach to each other.
D.
The pull of myosin on actin causes the motor neuron to send a nerve impulse.