Antonym of IMPOUND

Answer: Option D

Impound : seize and take legal custody of (something, especially a vehicle, goods, or documents) because of an infringement of a law.
Generate : produce or create.
Strengthen : make or become stronger.
Stimulate : raise levels of physiological or nervous activity in (the body or any biological system).
Release : allow or enable to escape from confinement; set free.

Antonym of Impound is Release