Which of the following is an example of moving properly for calf raises?
A : Raising the heels, leaning slightly forward with knees and hips flexed
B : Lowering the heels, leaning slightly forward with feet approximately shoulder width apart
C : Raising and lowering the heels, leaning slightly backward with feet approximately shoulder width apart
D : Raising and lowering the heels, leaning slightly forward with feet approximately shoulder width apart