NDA General Ability Question (2025) — Solution

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Volcanic ash consists of fine particles of fragmented volcanic rock and glass. When this ash is carried by running water and deposited as a sedimentary layer, it undergoes compaction and cementation over time. The lithified rock formed from the consolidation of volcanic ash is known as tuff. Basalt is an extrusive igneous rock, lapilli refers to small volcanic fragments, and slate is a metamorphic rock. Answer: Tuff