Which type of sensory receptor is responsible for monitoring blood pressure by responding to stretch in the walls of blood vessels?

Baroreceptors are specialized sensory receptors specifically designed to detect changes in blood pressure by responding to the stretching of blood vessel walls. They are located primarily in the arteries, particularly in areas such as the carotid sinus and the aortic arch. When blood pressure rises, the walls of these blood vessels stretch, and baroreceptors respond by firing action potentials to the central nervous system, signaling that blood pressure has increased. This information is vital for the body to maintain homeostasis, as it allows for adjustments in heart rate and blood vessel diameter to stabilize blood pressure.

The other types of receptors listed serve different functions. Thermoreceptors detect changes in temperature, photoreceptors are involved in vision by responding to light, and mechanoreceptors can sense mechanical changes such as touch or pressure but are not specifically tuned to blood pressure regulation. Thus, baroreceptors are the most suitable choice for the function described in the question.