Coal has been mainly formed by

Options

A. Bryophytes
B. Pteridophytes/pteridosperms
C. Angiosperms
D. Algae

Answer

**Step-by-Step Solution:**

1. **Understanding Coal Formation**: Coal is formed from the remains of ancient plants that lived in swampy, warm, and humid regions.

2. **Plant Types**: The main types of plants that contributed to coal formation include various groups, but we need to identify which among the given options is primarily responsible.

3. **Swamp Environment**: In these swampy areas, plants grow, die, and their remains accumulate in waterlogged conditions, preventing complete decomposition.

4. **Layering Process**: As more plants die, their remains pile up in layers. Over millions of years, these layers are subjected to heat and pressure.

5. **Transformation to Peat and Coal**: The accumulated plant material undergoes chemical and physical changes due to heat, pressure, and microbial activity, transforming first into peat and eventually into coal.

6. **Identifying the Correct Plant Group**: Among the options provided:
- Bryophytes (mosses) are not significant contributors to coal.
- Angiosperms (flowering plants) are more recent and not the primary source of coal.
- Algae are aquatic and do not contribute significantly to coal formation.
- Pteridophytes (ferns) and pteridosperms (seed ferns) are the main contributors to coal deposits.

7. **Conclusion**: Therefore, the correct answer is that coal has mainly formed by **pteridophytes or pteridosperms**.

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