Answer:
The correct answer is: form cross bridges with the actin molecules of the thin filaments.
Step-by-step explanation:
The sarcomere makes up the unit of the striated muscle tissue, and is the structure responsible for the contractility of this tissue. Sarcomeres are composed of two types of filaments: thick filaments formed by myosin molecules, and thin filaments that are formed by actin molecules. In order to contraction to happen, the thin and the thick filaments move between one another in a coordinated manner to shorten the sarcomere and produce muscle contraction.
For muscle contraction to happen, myosin heads bind to the actin molecule by forming a cross-bridge with it -this happens when the actin-binding site that is commonly hidden by the proteins troponin and tropomyosin, is uncovered thanks to the arrival of calcium ions-. This binding allows the sliding mechanism that will end up shortening the sarcomere.