Ionization Energy of Lanthanides

Q. La, Gd and Lu have abnormally low third ionisation enthalpy values. Why? ​

Q. Read the assertion and reason carefully to mark the correct option out of the options given below:

(a)If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)If assertion is true but reason is false.

(d)If assertion is false but reason is true.
Assertion : EV(M${}^{2+}$/M) value for copper is positive (+0.34V).
Reason : High ionization enthalpy and low heat of hydration energy

1. a
2. b
3. c
4. d