Final answer:
Sarin is the nerve agent listed among the given options. It inhibits acetylcholinesterase, causing overstimulation of muscles and paralysis.
Step-by-step explanation:
Among the substances listed, sarin is a nerve agent. Nerve agents, such as sarin (GB), soman (GD), and tabun (GA), are a class of organic chemicals that act as acetylcholinesterase inhibitors.
These agents prevent the enzyme acetylcholinesterase from breaking down acetylcholine, leading to an overstimulation of muscles, paralysis, and potentially death due to asphyxiation. Sarin, specifically, is an extremely potent toxin that was released in the Tokyo subway system in 1995 by the Japanese terrorist group Aum Shinrikyo, resulting in multiple fatalities and injuries.