During the process of ecological succession, the changes that take place in communities are

Options

A. orderly and sequential
B. random
C. very quick
D. not influenced by the physical environment

Explanation

### Step-by-Step Solution:

1. **Definition of Ecological Succession**:
- Ecological succession refers to the gradual and predictable changes in the species composition of a given area over time.

2. **Nature of Changes**:
- The changes that occur during ecological succession are orderly and sequential. This means that the changes follow a specific order and are not random.

3. **Concept of Seral Stages**:
- The entire sequence of communities that successively change in an area is referred to as a "seral" or "seral stages." Each stage represents a different community that arises as succession progresses.

4. **Influence of Physical Environment**:
- Ecological succession is influenced by the physical environment. Factors such as climate, soil type, and availability of resources play a significant role in determining the types of species that can thrive in a community.

5. **Exclusion of Incorrect Options**:
- Options that suggest changes are random, very quick, or not influenced by the physical environment are incorrect. Ecological succession is characterized by its predictability and the influence of environmental factors.

6. **Conclusion**:
- Therefore, the correct understanding of ecological succession is that it involves gradual, predictable, and orderly changes in species composition influenced by the physical environment.