Nerve Agents are best described as substances that attack the nervous system and affect muscle control, vision, heart, and lung functions.

• A. Blister Agents
• B. Nerve Agents
• C. Blood Agents
• D. Choking Agents

Answer: (B)

This question describes substances that disrupt the nervous system, leading to problems with muscle control, vision, heart rate, and breathing. Nerve agents do exactly that by inhibiting acetylcholinesterase, the enzyme that normally breaks down acetylcholine. When this enzyme is blocked, acetylcholine builds up at nerve junctions and autonomic sites, causing excessive and sustained stimulation of muscles and glands. That results in uncontrolled muscle activity, excessive secretions, pinpoint pupils, and severe respiratory effects from both airway constriction and weakness of the breathing muscles. In severe cases, seizures, coma, and death can follow. The other classes produce different primary effects: blister agents mainly cause skin and eye damage; blood agents disrupt cellular respiration; choking agents irritate the lungs and can cause pulmonary edema. Because the description points to nervous system attack and subsequent impacts on muscle control, vision, heart, and lungs, it matches nerve agents.