7. All of the following statements about muscle contraction are true EXCEPT； (A) The ends of actin filaments move closer together (B) Calcium-troponin binding precedes actin-myosin binding (C) Calcium-tropomyosin binding precedes actin-myosin binding (D) ATP hydrolysis precedes actin-myosin binding (E) The length of myosin filaments does not change