Explanation:

- Option 1: Ralph Linton

- Ralph Linton is known for his work on "status and role" in sociology, but he did not specifically use the concept of "recruitment roles."

- Option 2: Talcott Parsons

- Talcott Parsons contributed to the theory of social roles and social systems. He focused on role-sets and their functions, not directly on "recruitment roles."

- Option 3: S.F. Nadel

- S.F. Nadel is credited with introducing the idea of "recruitment roles," especially in his work on social structure and roles within it.

- Option 4: E. Hoffman

- E. Hoffman is not a prominent figure in the conceptualization of recruitment roles in sociology.

Correct Answer: Option 3: S.F. Nadel