**Core Concept**
Baroreceptors are specialized sensors located in the walls of blood vessels, particularly in the carotid sinus and aortic arch, that detect changes in blood pressure and volume. They play a crucial role in regulating blood pressure through the baroreflex mechanism.

**Why the Correct Answer is Right**
Baroreceptors respond to increased stretching of the arterial walls due to high blood pressure by activating mechanoreceptors, which in turn activate the afferent neurons to send signals to the brainstem. The brainstem processes these signals and responds by activating the parasympathetic nervous system, which increases vagal tone and reduces sympathetic outflow, ultimately leading to vasodilation and a decrease in blood pressure. Conversely, during hypotension, baroreceptors are stimulated less, leading to a decrease in parasympathetic activity and an increase in sympathetic activity, resulting in vasoconstriction and an increase in blood pressure.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe the primary function of baroreceptors.
**Option B:** This option is incorrect because it misidentifies the location of baroreceptors; while they are indeed found in blood vessels, they are specifically located in the carotid sinus and aortic arch.
**Option C:** This option is incorrect because it describes a different type of receptor; chemoreceptors are responsible for detecting changes in blood pH, oxygen, and carbon dioxide levels.

**Clinical Pearl / High-Yield Fact**
Baroreceptors are responsible for the body's ability to maintain blood pressure homeostasis, and dysfunction of these receptors can lead to conditions such as orthostatic hypotension and hypertension.

**Correct Answer: C. High-pressure receptors located in the walls of blood vessels.**