Ecesis is :

Options

A. establishment of a plant in a new place
B. a condition of equilibrium
C. climax
D. invasion of a number of plants

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Ecesis":**
Ecesis refers to the process of establishment of a species in a new habitat. This can apply to both plants and animals.

2. **Analyzing the Options Provided:**
The question provides four options:
- A) Establishment of plant in a new place
- B) A condition of equilibrium
- C) Climax
- D) Invasion of a number of plants

3. **Identifying the Correct Definition:**
Among the options, the first one (establishment of plant in a new place) directly aligns with the definition of ecesis. The other options do not accurately describe ecesis:
- Option B (a condition of equilibrium) refers to a stable state in an ecosystem, not the establishment of a species.
- Option C (climax) refers to a mature stage of ecological succession, which is different from ecesis.
- Option D (invasion of a number of plants) implies a different concept, often associated with invasive species rather than the establishment of a species.

4. **Conclusion:**
Therefore, the correct answer to the question "Ecesis is:" is **A) Establishment of plant in a new place**.

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