Order of basic processes involved in succession is

The correct option is "nudation -> invasion -> completion and co action -> reaction -> stabilization".

Ecological succession is the gradual and predictable process by which the structure of a biological community evolves over time. The correct sequential order of the basic processes involved in ecological succession is explained step-by-step below:

1. Nudation:
This is the initial stage, which involves the development of a bare area or a naked site without any form of life. This can occur due to natural factors such as landslides, volcanic eruptions, floods, or human activities like clearing forests.

2. Invasion:
This is the successful establishment of a species in the bare area. It includes three sub-steps:
- Migration (Dispersal): Seeds, spores, or other propagules of species reach the new bare area via wind, water, or animals.
- Ecesis (Establishment): The germinated seeds or spores adjust to the new environmental conditions, grow, and establish themselves.
- Aggregation: The successfully established individuals reproduce, increasing their population size and forming groups or aggregations in the area.

3. Competition and Co-action:
As the population density of the colonizing species increases, both intra-specific (within the same species) and inter-specific (between different species) competition begins for limited resources such as space, nutrients, water, and light. The organisms also exert reciprocal effects on each other, known as co-action.

4. Reaction:
This is the most crucial stage of succession. The living organisms interact with and modify their physical environment. These modifications (such as changes in soil pH, organic matter accumulation, or microclimate) often make the environment less favorable for the existing community and more suitable for the invasion of new, more demanding species.

5. Stabilization (Climax):
This is the final stage of succession where the community reaches a state of equilibrium with the local climate. This stable, self-perpetuating, and final community is called the climax community, representing the stabilization stage.