Which English verb means 'to weaken'?

• A. to strike
• B. to trigger
• C. to undersize
• D. to wear down

Answer: (D)

The main idea here is choosing a verb that conveys gradual weakening. The best fit is to wear down, a phrasal verb that describes something being weakened over time or through repeated use or pressure. It captures both physical wear (like a rope or cliff eroding) and abstract wear (such as patience or resistance diminishing). For example, continuous friction wore down the rope until it snapped, or years of stress wore down his resolve. The other verbs don’t express weakening: to strike means to hit; to trigger means to cause something to begin; and to undersize means to make something smaller than standard.