​_______ are neurochemicals that help modulate, or lessen, the experience of pain.

A) ​Endorphins
B) ​Interneurons
C) ​Glutamates
D) ​Proinflammatory cytokines

Endorphins are neurochemicals that are released in response to pain or stress and act as natural painkillers by binding to opioid receptors in the brain and spinal cord, thereby reducing the perception of pain. Interneurons are nerve cells that transmit signals between neurons and are involved in reflexes and information processing in the spinal cord. Glutamates are a type of neurotransmitter that is involved in learning and memory, while proinflammatory cytokines are proteins that promote inflammation and can exacerbate pain.