All of the Following Are Necessary for Contraction to Occur

Multiple Choice

All of the following are necessary for contraction to occur EXCEPT which one?

A) Calcium levels must increase in close proximity to the contractile proteins.
B) ATP must be present.
C) Troponin-tropomyosin complex must shift out of the way.
D) Cross-bridges must form between actin and myosin.
E) The troponin and tropomysin must slide relative to each other, shortening the sarcomere.