The muscle must change its contraction, wave summation and twitch mode.
Explanation:
Muscle tissue is important for the contraction and movement of an organism. Muscles contain important protein like actin, myosin and troppomyosin that helps in the movement of a particular part of a body.
While lifting a box, if someone put extra weight the muscle will shift from isometric to isotonic contraction. The muscle decreases the wave summation and turns to fast twitch mode for the continuous contraction and lifting the box.
I believe the correct answer among the choices listed above is option B. A gland secretes enzymes through a duct onto the surface of a body part is a salivary gland. It is under the classification of exocrine glands. Hope this answers the question.