Explanation:

- Option 1: Assimilation

- Assimilation refers to the process by which individuals or groups adopt the culture of another group, leading to integration.

- Option 2: Accommodation

- Accommodation involves modifying one's existing framework or understanding to incorporate new experiences or information.

- Option 3: Competition

- Competition typically involves opposing forces striving for the same goal, which can create divisions rather than integration.

- Option 4: Co-operation

- Co-operation is the act of working together towards a common goal, fostering integration through shared effort and understanding.