Difficulty: Hard
Correct Answer: None of these
Explanation:
Introduction / Context:This is a logical relations problem. “Whenever milk is kept in front of a child, the child cries” (I) indicates milk-in-front is a sufficient condition for crying. Statement II links hunger to crying (hunger ⇒ crying). Statement III links unhappiness to hunger (unhappy ⇒ hungry ⇒ crying). We must test each conclusion against these implications.
Given Data / Assumptions:
Concept / Approach:Translate to implications and test converses (which are generally invalid): from A ⇒ B we cannot infer B ⇒ A. None of the conclusions should introduce unstated converses/generalizations.
Step-by-Step Solution:
• (a) “When hungry, a child likes milk.” Hunger ⇒ liking milk is not stated or implied.• (b) “A child crying means unhappy.” We have unhappy ⇒ crying, but not the converse crying ⇒ unhappy; crying could be due to milk being present or other reasons.• (c) “A happy child does not cry.” Not given; a happy child could cry if milk is placed in front (I), or for other reasons.• (d) “An unhappy child usually cries.” III gives unhappy ⇒ hungry ⇒ crying (deterministic), but the option says “usually,” altering modality; though stronger certainty exists in premises, the wording mismatch and lack of “usually” premise makes this not a strict logical follow.Verification / Alternative check:Draw implication chain and confirm no converse or added modality sneaks in.
Why Other Options Are Wrong:They assume converses or add preferences/modalities not in premises.
Common Pitfalls:Assuming crying implies unhappy; mixing up necessity/sufficiency.
Final Answer:None of these.
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