<prompt> Tetanizing stimulation of the muscle causes a sustained forceful contraction due to:Recruitment phenomenonFailure of Ca removal from the sarcoplasmSummation of the stimuliBeneficial effect  <response>: Tetanizing stimulus means high-frequency stimulation. When stimuli are applied in quick succession, there is release of Ca, with each stimulus, from the SR into the sarcoplasm. For the muscle to relax, this Ca should be pumped back into the SR, which fails to happen due to the rapid succession of stimuli. The muscle remains in a sustained state of contraction, called as tetanus. 