Final answer:
Flushing of the neck and tachycardia are most likely adverse effects of antihypertensives, particularly vasodilators such as nitrates.
Step-by-step explanation:
The adverse effects of flushing of the neck and tachycardia can be associated with various drugs, but in the context of the options provided, these symptoms are most likely linked to antihypertensives, specifically the ones that can cause vasodilation. Vasodilators can induce flushing as they expand blood vessels. Tachycardia can occur as a compensatory mechanism when blood pressure drops due to the vasodilation effect of the antihypertensive medication. The question is most likely referring to the adverse effects of nitrates, which are often used for treating conditions like angina by dilating blood vessels, and as a result, can cause flushing and increased heart rate.
For reference, epinephrine is used to counteract the effects of anaphylactic shock while angiotensin II is a known vasoconstrictor. Diuretics, which are sometimes classified as anti-hypertensives, work on the loop of Henle and inhibit the reabsorption of Na+ and Cl-, but are more associated with the excretion of fluid than with direct flushing or tachycardia.