Which root refers to the sensation of pain?

The root that refers specifically to the sensation of pain is "alges/o." This root is derived from the Greek word "algos," meaning pain. It is commonly used in medical terminology to describe conditions or sensations associated with pain. For instance, terms like "analgesic," which refers to a substance that alleviates pain, utilize this root to convey its meaning effectively.

The other roots provided do not pertain to pain sensations. "Amni/o" relates to the amniotic sac surrounding the fetus; "aer/o" refers to air or gas; and "alb/o" denotes a color, specifically white. Understanding the distinct meanings of these roots helps to clarify their applications in medical terms, reinforcing the recognition that "alges/o" is the correct choice in the context of pain sensations.