Tetanus is a (n) : a. muscle contraction of sustained force resulting from repeated action potentials. b. contraction where the muscle does not change length. c. abnormal muscle contraction. d. contraction that slowly increases in force. e. contraction caused by a single action potential.

Answer: muscle contraction of sustained force resulting from repeated action potentials. (Option A)

Explanation: Tetanus is also called physiologic tetanus. Tetanus refers to the contraction of the muscle, which is established when the motor nerve that supply nerves to a skeletal muscle produces action potentials at a very high degree.

However, tetanic contraction is usually a normal process (such as when carrying a heavy box). Also, muscles can be shorten, lengthen or remain constant length during tetanic contractions.