Which word best fits the definition 'sudden, intense'?

• A. Abstain
• B. Adverse
• C. Acute
• D. Ambivalent

Answer: (C)

The concept being tested is finding a word that conveys something happening quickly with strong intensity. Acute is the term that fits both the rapid onset and the strong impact, as in acute pain or an acute illness, which describes something intense that comes on suddenly and is often evident right away. The other words don’t match that sense: abstain means to refrain from doing something, not about intensity or timing; adverse describes something harmful or unfavorable but not the sudden, sharp onset; ambivalent means having mixed feelings, which also doesn’t capture the idea of sudden intensity. So, acute is the best fit.