Final answer:
The receptors that cause a quick withdrawal from touching a hot plate when you feel pain are nociceptors, which detect potentially damaging stimuli such as high temperature.
Step-by-step explanation:
When you touch a hot plate, the receptors that cause you to remove your hand from the hot plate to stop the pain are nociceptors. These are activated in the brain and spinal cord to send messages in response to the stimuli of touching the hot plate. Nociceptors are sensory neurons in the skin that detect pain from potentially damaging stimuli such as extreme heat. A reflexive withdrawal, like pulling your hand back from a hot plate, is initiated via a reflex arc.
Nociception begins at the sensory receptors, and it does not become the perception of pain until it is communicated to the brain. The reflex arc can allow for a quick response to a painful stimulus without the need for that signal to be processed by the brain. Thus, the correct answer to the question is A) Nociceptors.