The break down of detritus into smaller particles is called as:

The correct answer is Option (2) → Fragmentation

Decomposition is the breakdown of detritus (dead plant and animal matter) into simple inorganic substances. It takes place in steps: fragmentation, leaching, catabolism, humification and mineralisation. The first step is fragmentation, in which detritivores such as earthworms break detritus into smaller particles.

(1) Decomposition — Incorrect. Decomposition is the name of the whole process, not of this first step.

(2) Fragmentation — Correct. Breaking detritus into small particles is fragmentation.

(3) Mineralisation — Incorrect. In mineralisation, humus is broken down further by microbes to release inorganic nutrients.

(4) Humification — Incorrect. Humification forms humus, a dark substance that resists microbial action and decomposes very slowly.

Note: A similar question was also asked in CUET (UG) 2025 on 28-05-2025 (Slot 1).

NCERT Extract:
Decomposition – …