Primary succession occurs on

Options

A. area destroyed due to fores fire
B. newly formed river delta
C. harvested crop field
D. all of these.

Explanation

**Step-by-Step Solution:**

1. **Understanding Succession**: Begin by defining what succession means in an ecological context. Succession refers to the gradual process of change and replacement in the species composition of an ecological community over time.

2. **Types of Succession**: Identify the two main types of succession: primary and secondary.
- **Primary Succession** occurs in lifeless areas where no soil exists, such as after a volcanic eruption or on bare rock.
- **Secondary Succession** occurs in areas where a disturbance has destroyed an existing community but soil and some organisms still remain, such as after a forest fire or flood.

3. **Analyzing the Options**: Review the options given in the question:
- **Area destroyed due to forest fire**: This is incorrect for primary succession as it indicates that a community existed before the fire.
- **Newly formed river delta**: This is a correct example of primary succession because it is a new area where no previous community exists.
- **Harvested crop field**: This typically represents a disturbed area where secondary succession may occur, as the soil and some organisms remain.
- **All of these**: This option cannot be correct since not all the provided options are examples of primary succession.

4. **Conclusion**: Based on the analysis, the only correct answer that represents primary succession is the "newly formed river delta."

**Final Answer**: Primary succession occurs on a newly formed river delta.

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