Fill in the blank with the correct word from the given options:-

Research has proved the significance of leading a structured life with enormous evidence to prove that mental fatigue can actually ____ life.

curtail

The correct answer is Option (2) → curtail

The context of the sentence contrasts the significance of a structured life (which generally promotes health and longevity) with the negative impact of mental fatigue. Therefore, the verb needed must describe a negative action on life duration.

• Curtail: Means to reduce in extent or quantity; impose a restriction on. In this context, it means to shorten life. This fits the implied negative consequence of fatigue.

• Produce: Means to create or manufacture. (Irrelevant.)

• Prolong: Means to extend the duration of. (This is the antonym of the intended meaning.)

• Procure: Means to obtain (something), especially with care or effort. (Irrelevant.)