Question

Four students-A, B, C, D-choose one subject each: History, Math, Science, English. A does not choose History. B does not choose Math. C does not choose English. Who chooses Science?

• A. A
• B. B
• C. C
• D. D
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Hint:

In subject assignment questions, use constraints to eliminate options and test one subject assignment to find consistent matches.

Answer 1

The Correct Option is A

- Step 1: List constraints. A not History. B not Math. C not English. Each chooses a different subject. 
- Step 2: Assign subjects. Subjects: History, Math, Science, English. B not Math, so B has History, Science, or English. C not English, so C has History, Math, or Science. A not History, so A has Math, Science, or English. 
- Step 3: Test Science. Assume A has Science. Then: B has History or English, C has History or Math, D gets the remaining subject. 
- Step 4: Assign remaining. If B has History, C has Math (not English), D has English. Check: A-Science, B-History, C-Math, D-English. Constraints: A not History (satisfied), B not Math (satisfied), C not English (satisfied). 
- Step 5: Verify other possibilities. If B has English, C has Math, D has History, A has Science. Valid. Science consistently goes to A. 
- Step 6: Final conclusion. Option (1) A is the correct answer.