Question

Five people-A, B, C, D, and E-are seated in a row. A is not next to B. C is next to D. E is not at the ends, who can be at the leftmost end (position 1)?

• A. A
• B. C
• C. E
• D. B
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Hint:

For end-position questions, eliminate candidates restricted from ends and test remaining ones with all constraints to confirm validity.

Answer 1

The Correct Option is A

- Step 1: Recall constraints. Five seats (1 to 5). A not next to B. C next to D. E not at ends (so E in 2, 3, or 4).
- Step 2: Identify leftmost end. Position 1 is the leftmost end. E cannot be in 1 (not at ends).
- Step 3: Test candidates for position 1. Possible candidates: A, B, C, D.
- Step 4: Test A in position 1. If A is in 1, B cannot be in 2 (A not next to B). E in 2, 3, or 4. C and D next to each other, e.g., 4 and 5. Example: 1-A, 2-E, 3-B, 4-C, 5-D. Check: A not next to B, C next to D, E not at ends. Valid.
- Step 5: Test others. B in 1: B not next to A, but similar arrangements work. C in 1: C next to D (in 2), E in 3 or 4, A and B placed without adjacency. Example: 1-C, 2-D, 3-E, 4-A, 5-B. Valid. D in 1 also works similarly.
- Step 6: Check options. E cannot be in 1 (option 3 invalid). A, B, C are possible, but A is option (1).
- Step 7: Final conclusion. Option (1) A is correct, as A can be at the leftmost end.
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