Which statement concerning in twitch summation is correct?

Question

Quizplus · Accepted Answer

Twitch summation occurs when a second stimulus is applied to a muscle fiber before it has completely relaxed from the first stimulus. This causes a second twitch that adds on to the first, resulting in stronger muscle contractions. However, if the second stimulus is applied before the filaments have completely returned to their resting position, the resulting contraction will be weaker than if the muscle had fully relaxed before being stimulated again. Therefore, statement B is correct. Statements A, C, and D are incorrect because they do not accurately describe twitch summation.

Which Statement Concerning in Twitch Summation Is Correct