Passage

Directions for the following 3 (three) items : Consider the given information and answer the three items that follow. A, B, C, D, E, F and G are Lecturers from different cities—Hyderabad, Delhi, Shillong, Kanpur, Chennai, Mumbai and Srinagar (not necessarily in the same order) who participated in a conference. Each one of them is specialized in a different subject, viz., Economics, Commerce, History, Sociology, Geography, Mathematics and Statistics (not necessarily in the same order). Further 1. Lecturer from Kanpur is specialized in Geography 2. Lecturer D is from Shillong 3. Lecturer C from Delhi is specialized in Sociology 4. Lecturer B is specialized in neither History nor Mathematics 5. Lecturer A who is specialized in Economics does not belong to Hyderabad 6. Lecturer F who is specialized in Commerce belongs to Srinagar 7. Lecturer G who is specialized in Statistics belongs to Chennai

Who is specialized in Geography?

(a) B ✓ UPSC's answer
(b) D
(c) E
(d) Cannot be determined as data are inadequate

Why the answer is (a)

• Fixed by the clues: C Delhi (Sociology), D Shillong, F Srinagar (Commerce), G Chennai (Statistics), A Economics.

• The cities left for A, B and E are Hyderabad, Kanpur and Mumbai. The Kanpur lecturer teaches Geography, so A (Economics) is not from Kanpur, and A is not from Hyderabad: A is from Mumbai.

• The subjects left for B, D and E are History, Mathematics and Geography. B teaches neither History nor Mathematics, so B teaches Geography, and B is from Kanpur; E is from Hyderabad.

• So B specialises in Geography, option (a).

Why the other options are wrong

(b) D: D is from Shillong, but the lecturer from Kanpur is specialized in Geography, and D's subject is not determined to be Geography in the final deduction where B takes it.
(c) E: E is from Hyderabad (since B is from Kanpur), and the lecturer from Kanpur is specialized in Geography, so E is not specialized in Geography.
(d) Cannot be determined as data are inadequate: The data is sufficient to determine that B is the lecturer from Kanpur who specializes in Geography.

Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2017, held on 18 June 2017. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.