Granite is almost impervious ______ acid-rain damage.

Concept: An adjective often governs a fixed preposition that cannot be chosen by meaning alone — it is set by collocation (the conventional word partnership). The adjective “impervious” (meaning “unable to be affected or penetrated”) is conventionally paired with the preposition “to” when naming what something resists.

Application: In “Granite is almost impervious ______ acid-rain damage,” the blank links the adjective “impervious” to the thing it resists (acid-rain damage). The established collocation is “impervious to”, so the sentence reads “Granite is almost impervious to acid-rain damage” — granite is largely unaffected by acid rain.

• “to” — the standard partner of “impervious”; it introduces what is being resisted, giving a complete, idiomatic sentence.

• “by” — marks the agent of a passive verb (“damaged by”), but “impervious” is an adjective, not a passive verb, so “by” does not fit here.

• “with” — signals accompaniment or instrument (“filled with”); it is not the preposition this adjective takes.

• “of” — expresses possession or composition (“made of”); it is not the fixed partner of “impervious.”

Cross-check: Replace the noun and the pairing still holds — “impervious to criticism,” “impervious to heat,” “impervious to water.” The preposition stays “to” regardless of what follows, confirming it as the correct collocation.