Explanation:

- Functionalism is a sociological perspective that sees society as a system of interconnected parts working together for stability.

- Emile Durkheim (Option 2) is known for establishing functionalism but primarily focused on social facts, solidarity, and collective conscience.

- Talcott Parsons (Option 3) advanced functionalism, emphasizing social systems and their needs, but did not focus much on dysfunctions.

- Robert Merton (Option 4) introduced the idea that not all parts of society are functional.

- He added concepts of dysfunctions and manifest/latent functions to functionalism.

- Karl Marx (Option 1) focused on conflict theory and class struggles, differing from functionalism.