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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 first ionisation enthalpy decreases across a period. Reason R: The increasing nuclear charge outweighs the shielding across the period. In the light of the above statements, choose the most appropriate from the options given below :

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

Correct answer: A is false but R is true

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