The question pertains to identifying methods that can ensure participatory communication. Let's analyze each of the given options:

• Community Radio: This is a powerful tool for participatory communication as it engages community members and provides a platform for voices that may not otherwise be heard. Community radio stations are typically run by communities, for communities, and often address local issues and promote local culture. Therefore, Community Radio supports participatory communication.
• Participatory Video: This method involves community members creating their own films to express their perspectives and share their stories. It is highly interactive and encourages community involvement, making it an excellent tool for participatory communication.
• Street Theatre: This form of live performance is often used to engage audiences directly in public spaces. It invites audience interaction and can raise awareness on social issues, making it a participatory form of communication.
• Public Speeches: While public speeches can be a part of public communication, they typically involve one person addressing a crowd without direct interaction from the audience. Thus, it might not fully encompass the participatory aspect compared to the other methods listed. It usually involves one-way communication unless structured in a way that allows for interaction and engagement.

Based on the above analysis:

• Option I, II, and III (Community Radio, Participatory Video, and Street Theatre) ensure participatory communication.
• Option IV (Public Speeches) does not inherently ensure participatory communication as it is often a one-way form of communication.

Therefore, the correct answer is: