A nursing student is helping to care for a patient who takes verapamil for stable angina. The nurse asks the student to explain the purpose of verapamil in the treatment of this patient. Which statement by the student indicates a need for further teaching?

a."It relaxes coronary artery spasms."
b."It reduces peripheral resistance to reduce oxygen demands."
c."It reduces the heart rate, AV conduction, and contractility."
d."It relaxes the peripheral arterioles to reduce afterload."