GATE CS 2016 Set 2 QGA-01 — General Aptitude

To choose the correct option, we need to analyze the use of definite (the) and indefinite (a/an) articles in the context of the sentence:

1. "a security guard" vs. "the security guard": A university typically employs multiple security guards. Since he was one of many such guards, the indefinite article "a" is appropriate. Using "the security guard" would incorrectly imply he was the sole security guard at the entire institution.
2. "at the university" vs. "at a university" vs. "at university":
   • "the university" is correct because it refers to a specific, contextually understood university (likely the one in the same city where he is now the Municipal Commissioner).
   • "at a university" is too vague for describing a past employment location in this context.
   • "at university" is an idiomatic phrase used to describe someone's status as a student (e.g., "She is studying chemistry at university"), not as a workplace for a staff member.

Thus, the complete and grammatically correct sentence is:
"The man who is now Municipal Commissioner worked as a security guard at the university."