Corruption stalks every sphere of national life.

Answer: Option A

Pervades : (especially of a smell) spread through and be perceived in every part of.
Penetrates : go into or through (something), especially with force or effort.
Pollutes : contaminate (water, the air, etc.) with harmful or poisonous substances.
Poisons : a substance that is capable of causing the illness or death of a living organism when introduced or absorbed.
Stalks : move silently or threateningly through (a place).

Synonym of Stalks is Pervades