Which of the following statements best defines acute toxicity?

• A. Toxic effects resulting from a single exposure
• B. Toxic effects that develop after repeated exposure over time
• C. Toxic effects that are only theoretical
• D. Toxic effects that occur only at high altitude

Answer: (A)

Acute toxicity is about the immediate or short-term toxic effects that appear after a single exposure. This focuses on what happens quickly when an organism encounters a toxic substance in one event, rather than over many events. That’s why the statement describing toxic effects arising from a single exposure best defines acute toxicity.

The other ideas describe different scenarios: effects that develop after repeated exposure over time point to chronic toxicity, not acute; toxicity that’s only theoretical isn’t about real observed effects; and altitude isn’t a factor in defining acute versus chronic toxicity.