Regarding a coronary blood flow:

• A. systolic blood flow in subendocardial arteries is greater than in the epicardial
• B. less than 50% of oxygen is removed during passage when in the resting state
• C. the coronary circulation is well supplied by parasympathetic vasodilatory fibres
• D. sympathetic vasoconstrictory fibres predominate in epicardial vessels
• E. none of the above