In the days before the internet, librarians served as the gatekeepers of information, organizing books and guiding researchers. Their role was considered _______ to the functioning of a university, as they ensured that students could access the knowledge required for their studies.
Which choice completes the text with the most logical and precise word or phrase?
incidental
vital
optional
theoretical
Correct Answer: B
Choice B is the best answer. The text states they "ensured that students could access" knowledge. This makes their role essential. "Vital" means absolutely necessary or important.
Choice A is incorrect because "incidental" means minor. Choice C is incorrect because "optional" means not required. Choice D is incorrect because "theoretical" means based on theory, not practice.