Final answer:
Vasopressors are medications that cause vasoconstriction and include phenylephrine, ephedrine, and vasopressin. Thus, the correct answer to the student's question is E) A and B.
Step-by-step explanation:
Vasopressors are agents that induce vasoconstriction, leading to an increase in blood pressure by constricting blood vessels. They are pharmacological agents used to elevate blood pressure in various clinical situations, such as in the case of severe hypotension or shock. Vasopressors include medications such as phenylephrine, ephedrine, and vasopressin, among others. These medications work by different mechanisms to induce vasoconstriction, primarily through the stimulation of adrenergic receptors or the mimicking of the body's own chemicals such as epinephrine and norepinephrine. On the other hand, substances like nitric oxide, natriuretic hormones, and bradykinin typically cause vasodilation, which leads to the relaxation and widening of blood vessels. Notably, angiotensin II is known to be a potent vasoconstrictor. In terms of medication, substances like nitroprusside, nitroglycerin, and nicardipine are vasodilators and not classified as vasopressors. Therefore, the correct answer to the question is E) A and B, as vasopressors cause vasoconstriction and include phenylephrine, ephedrine, and vasopressin.