Which of the following is considered a biological toxin?

• A. Chlorine gas
• B. Sarin
• C. Anthrax
• D. Buried explosives

Answer: (C)

The correct answer is anthrax, which is classified as a biological toxin due to its nature as a pathogen that can cause severe illness or death in humans and animals. Anthrax is caused by the bacterium Bacillus anthracis, and it can be released in various forms, such as spores, which can be inhaled, ingested, or introduced through the skin. Its use as a bioweapon highlights its potential for mass harm as it can spread rapidly and cause widespread fear and disruption.

In contrast, chlorine gas is a chemical irritant commonly used in disinfection processes, but it is not a biological toxin. Sarin is a highly toxic nerve agent and is classified as a chemical weapon, not biological. Buried explosives refer to physical devices designed to detonate, which are neither biological nor toxic in the sense used to describe infectious agents or toxins. Thus, anthrax is the only option among the provided choices that qualifies as a biological toxin due to its pathogenic and infectious properties.