What does volatile mean?

• A. Vaporizing or evaporating quickly
• B. The sound level
• C. The amount of space taken up by something
• D. Likely to change suddenly and unexpectedly or suddenly become violent or angry; unstable; explosive

Answer: (D)

Volatile conveys a sense of instability and quick, unpredictable change. In everyday use, it describes people or situations that can flip suddenly—someone’s temper that can flare up without warning or a situation that could explode into action at any moment. That immediate sense of unpredictability and potential for sudden change is what makes this the best fit.

There is a more technical sense, about substances that evaporate quickly, but the question is aiming at how the word is commonly understood in normal speech, where volatility means being unstable and prone to quick shifts. The other options don’t fit because they describe the sound level or the amount of space, which aren’t related to the idea of abrupt change or instability.