In Skeletal Muscle, an Incomplete Tetanus Would Result from

In skeletal muscle, an incomplete tetanus would result from

A) action potentials arriving at a rate fast enough for the intracellular Ca²⁺ levels to rise much higher than they would in a muscle twitch.
B) action potentials arriving at a rate fast enough for sarcomeres to generate force while the elastic components of the muscle are still stretched.
C) action potentials arriving so quickly that there is no fluctuation in intracellular Ca²⁺ levels.
D) many, but not all, of the thin filaments being activated to permit cross-bridge formation.