Given below are two statements : one is labelled as Assertion \((A)\) and the other is labelled as Reason \((R)\) Assertion \((A)\) : The first ionization enthalpy of \(3 d\) series elements is more than that of group \(2\) metals Reason \((R)\) : In \(3d\) series of elements successive filling of d-orbitals takes place. In the light of the above statements, choose the correct answer from the options given below :

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