See the following figure describing musle contraction.

Identify A, B,C, D and E

Options

A. A - Cross bridge, B - Cross bridge formation, C - Sliding/ rotation, D - ADP, E - Breaking of cross bridge
B. A - Cross bridge, B - Breaking of cross bridge, C - Sliding/ rotation, D - Cross bridge formation, E - AMP
C. A - Cross bridge, B - Cross bridge formation, C - Sliding/ rotation, D - Breaking of cross bridge, E - ATP
D. A - Cross bridge, B - Cross bridge formation, C - Breaking of cross bridge, D - Sliding (rotation), E – ATP

Answer

C

Explanation

A = Cross bridge, a cross bridge form between the actin and myosin head triggering contraction.
B= Cross bridge formation, as long as ATP is available, the muscle fiber is continue to shorten.
C = rotation, the rotation only occur when myosin binding site on the actin filament are exposed by a series of step that begin with Ca entry into the sarcoplasm.
D = Breaking of cross bridge, in the presence of ATP, the head detach from actin.
E = ATP, in the absence of ATP, myosin head not detach from actin.