Anursing student is caring for a patient who has been taking morphine sulfate for pain for 2 weeks. the nursing student shows an understanding of pharmacodynamic tolerance by describing it to the instructor in what way?
a "it is a form of tolerance that is a reduction in drug responsiveness brought on by repeated dosing over a short period."
b "it affects the minimum effective concentration."
c "it is a drug response caused by psychologic factors, not by biochemical or physiological properties."
d "it is a condition in which the patient requires increased doses of morphine sulfate to achieve pain relief."