Identify a dark-coloured amorphous substance that is highly resistant to microbial action and undergoes decomposition at an extremely slow rate.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. Humus.
- Humus is dark, organic material that forms in soil when plant and animal matter decays.
- When plants drop leaves, twigs, and other material to the ground, it piles up. This material is called leaf litter. When animals die, their remains add to the litter.
- Over time, all this litter decomposes.