Which of following is a valid conclusion from the premise. "Nigeria footballers are good footballers"?

Analyze the question: This is a logic (validity of arguments) question. The premise is "All Nigerian footballers are good footballers." We need the conclusion that follows necessarily.

Concept: A statement "All A are B" means A is a subset of B.

• If x is in A, then x is in B (valid).
• If x is in B, we cannot conclude x is in A (invalid, since B may contain members outside A).

Here, A = Nigerian footballers, B = good footballers.

Check each option:

• A. "Joseph plays football in Nigeria, so he is a good footballer." Playing football in Nigeria does not make someone a Nigerian footballer (he could be a foreigner), so this is not valid.
• B. "Joseph is a good footballer, so he is a Nigerian footballer." This reverses the premise (B to A), so it is invalid. Good footballers exist in other countries too.
• C. "Joseph is a Nigerian footballer, so he is a good footballer." Joseph is in A, and A is inside B, so Joseph is in B. This is valid.
• D. "Joseph plays good football, so he is a Nigerian footballer." This is also the reversed (converse) form, so it is invalid.

Tip: In "All A are B" questions, only the argument that goes from A to B is valid. Beware of options that go from B back to A. This is the converse error, and examiners love to use it as a trap. Drawing a small circle (A) inside a bigger circle (B) quickly shows this.