Jeffery wants to locate reliable academic information on the effects of global warming and ways to conserve energy. What is the most efficient and effective search strategy to identify subject terms for a database search? Choose one of the following answers:

He can look for common related subject terms in a dictionary, thesaurus or encyclopedia.

He can look for relevant articles in the results list from a database search and scan the subject terms.

He can use Google Scholar to retrieve relevant articles and find common related subject terms.