Final answer:
Negative peak duration of a CMAP waveform provides information on the duration of the muscle's electrical response. This measurement helps evaluate the time muscles take to depolarize and repolarize, which is important in neuromuscular diagnostics.
Step-by-step explanation:
The measurement of negative peak duration of a CMAP waveform would yield the most information regarding the duration of muscle response. Compound Muscle Action Potentials (CMAPs) are used in electromyography to assess the health of muscles and the nerve cells that control them. The negative peak duration reflects the time it takes for all muscle fibers innervated by a nerve to depolarize and then repolarize.
Option A, P wave, is related to atrial depolarization. Option B, QRS complex, is indicative of ventricular depolarization. Option C, T wave, corresponds to ventricular repolarization. Option D is correct as atrial repolarization occurs but is not visible because it is masked by the QRS complex representing ventricular depolarization.