The nurse determines that the patient understands an important principle in the self-administration of nifedipine when the patient makes which statement?
a. "the use of antacids when taking the medication will enhance absorption."
b. "grapefruit juice may enhance the absorption of nifedipine."
c. "this drug will make my birth control pills ineffective."
d. "if i miss a dose, i should take two nifedipine capsules when i remember."