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Given below are two statements : one is labelled as - Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The ionic radii of O 2 – and Mg 2+ are same. Reason (R) : Both O 2– and Mg 2+ are isoelectronic species. In the light of the above statements, choose the correct answer from the options given below.

1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.

Correct answer: (A) is false but (R) is true.

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