The micro-organisms which convert the dead plants and animals to humus are known as :

Question

Accepted Answer

Explanation:

1. **Why Option 4 (Decomposers) is Correct:**
   Decomposers are micro-organisms, such as bacteria and fungi, that play a crucial role in the ecosystem by breaking down dead plants and animals. This process of decomposition converts organic matter into simpler substances, resulting in the formation of humus. Humus is a rich, organic component of soil that enhances its fertility and structure. Decomposers are essential for recycling nutrients back into the ecosystem, making them vital for maintaining ecological balance.

2. **Why the Other Options are Incorrect:**

- **Option 1 (Deforestation):** Deforestation refers to the clearing or thinning of forests by humans. It is not related to the conversion of dead plants and animals into humus. Instead, deforestation often leads to habitat destruction and a decrease in biodiversity.

- **Option 2 (Crown):** The crown of a tree is the upper part, including the branches and leaves. It is involved in photosynthesis and does not play a role in the decomposition process or the conversion of organic matter into humus.

- **Option 3 (Canopy):** The canopy is the layer formed by the leaves and branches of trees in a forest. While it provides habitat and regulates microclimates, it is not involved in the decomposition of dead organic matter into humus.

In conclusion, decomposers are the specific micro-organisms responsible for breaking down dead plants and animals into humus, making Option 4 the correct answer. The other options do not relate to this biological process.