3. The method of claim 1 , wherein based in part on each user of the one or more users have a threshold likelihood of knowing an answer to the search query based on information associated with that user by the social networking system comprises: retrieving user profiles and stored actions associated with one or more users of the social networking system; and selecting one or more of the identified users based on the associated user profiles, stored actions, and the search query.
3. The method of claim 1 , wherein based in part on each user of the one or more users have a threshold likelihood of knowing an answer to the search query based on information associated with that user by the social networking system comprises: retrieving user profiles and stored actions associated with one or more users of the social networking system; and selecting one or more of the identified users based on the associated user profiles, stored actions, and the search query. 4. The method of claim 3 , wherein the associated user profiles include explicitly stated user interests, implicit user interests, inferred user interests, and demographic information.