Where do A-delta fibers primarily terminate in Rexed's lamina?

A-delta fibers are myelinated nerve fibers that conduct fast pain and temperature sensations. In the spinal cord, they primarily terminate in Rexed's lamina I and V. Lamina I is responsible for processing nociceptive (pain-related) information, while lamina V plays a role in the integration of sensory input and the relay of pain signals.

The termination of A-delta fibers in both lamina I and V allows for a rapid response to painful stimuli, which is essential for protective reflexes. The fibers' involvement in these specific laminae facilitates the immediate perception of sharp pain and the initiation of reflex responses. Thus, the correct answer reflects the physiological pathway of pain signaling in the spinal cord, highlighting the roles of these particular laminae in processing fast pain sensations.