Which agent has the texture of motor oil, known for persistence in the environment?

• A. Sarin
• B. VX
• C. Mustard Gas
• D. Chlorine Gas

Answer: (B)

Texture and persistence go hand in hand for liquids that linger after a release. An agent described as having a motor-oil texture is thick and viscous, so it coats surfaces and stays put rather than evaporating away quickly. VX fits this profile: it’s a nerve agent with very low volatility, forming a dense, oily film that clings to skin and surfaces and can remain for a long time under many conditions. That combination of thick, oily consistency and long-lasting presence makes it the best match for the description. In comparison, sarin evaporates rapidly because it’s much more volatile, leaving little residue. Mustard gas is oily and can be persistent, but VX is typically noted for its especially viscous feel and greater environmental persistence. Chlorine gas, by contrast, is a gas and does not produce an oily surface residue, so it lacks the persistent surface contamination characteristic.