Detailed Instructions: In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Q: Question: The afferent neural activity of the peripheral nocioceptors is modulated in the dorsal horn of the marrow, which acts as a door that prevents or does not allow the passage of nerve impulses that come from the nocioceptors and the cortex, refers to?
Options: <1> The peripheral nervous system. <2> The theory of the door. <3> Chronic stress <4> The theory of climbing. <5> The biological process of relaxation.
A:
2