What is the response to enhance in the length of the right knee extensors in response to a quick tap applied to the right patellar tendon? An increase in the amount of
A. open channels associated with AMPA receptors in the plasma membranes of the right knee extensor muscle fibers.
B. calcium conductance in the axonal endings of the right knee extensor motor neurons.
C. open force-gated channels in the central axon terminals of IA muscle-spindle stretch receptor neurons whose peripheral terminals are in the right knee extensor muscle.