A ate grapes and pineapple; B ate grapes and oranges; C ate oranges, pineapple and apple; D ate grapes, apple and pineapple. After taking fruits, B and C fell sick. In the light of the above facts, it can be said that the cause of sickness was :
- (a) Apple
- (b) Pineapple
- (c) Grapes
- (d) Oranges ✓ UPSC's answer
Why the answer is (d)
• B ate grapes and oranges; C ate oranges, pineapple and apple. The only fruit common to both B and C is oranges.
• A ate grapes and pineapple, and D ate grapes, apple and pineapple. Neither A nor D ate oranges, and neither of them fell sick.
• Grapes were eaten by A, B, and D, yet A and D did not fall sick, so grapes cannot be the cause.
• Pineapple was eaten by A, C, and D, yet A and D did not fall sick, so pineapple cannot be the cause.
• Apple was eaten by C and D, yet D did not fall sick, so apple cannot be the cause.
• Oranges is the sole fruit shared by the two sick persons (B and C) and absent from the diets of the two healthy persons (A and D), so the answer is option (d).
Why the other options are wrong
- (a) Apple
- Apple was eaten by both C (sick) and D (not sick). Since D consumed apple and did not fall ill, apple cannot be the cause of sickness.
- (b) Pineapple
- Pineapple was eaten by A, C, and D. Since A and D consumed pineapple and did not fall ill, pineapple cannot be the cause of sickness.
- (c) Grapes
- Grapes were eaten by A, B, and D. Since A and D consumed grapes and did not fall ill, grapes cannot be the cause of sickness.
Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2016, held on 7 August 2016. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.