Which Statements Are True Regarding Cardiac Contractility

Which statements are true regarding cardiac contractility?

A) Cardiac contractility is the ability of the myocardium to stretch and contract.
B) The muscle filaments may be unable to change the force of contraction.
C) The stroke volume decreases as the preload increases.
D) The contractibility can also be influenced by preload.
E) The heart's workload increases as afterload increases.