Statements: All cows are animals. All deers are cows. Conclusions: I. All deers are animals. II. All animals are cows. Choose the correct option.

Difficulty: Easy

Correct Answer: Only conclusion I follows.

Explanation:

Introduction / Context:This is a straightforward chain of universal affirmatives and a check for an invalid converse. Such questions reinforce that subset relations do not reverse.

Given Data / Assumptions:

  • Cows ⊆ Animals.
  • Deers ⊆ Cows.

Concept / Approach:Transitivity of subset: If Deers ⊆ Cows and Cows ⊆ Animals, then Deers ⊆ Animals. The converse statement “All Animals are Cows” does not follow from “All Cows are Animals.”

Step-by-Step Solution:1) Combine inclusions: Deers ⊆ Cows and Cows ⊆ Animals ⇒ Deers ⊆ Animals (Conclusion I true).2) Test Conclusion II: “All animals are cows” would require Animals ⊆ Cows, which is the converse of a given premise and is not logically implied.

Verification / Alternative check:Model: Animals = {a1, a2}, Cows = {a1}, Deers = {a1}. Premises hold. But a2 ∈ Animals is not a cow, refuting Conclusion II while keeping I true.

Why Other Options Are Wrong:“Only II” and “Both” assert a converse fallacy. “Neither” ignores the valid transitive implication.

Common Pitfalls:Confusing subset with equality; “All Cows are Animals” does not say “only cows are animals.”

Final Answer:Only conclusion I follows.

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