Assertion( a) : Reactivity of transition elements decreases almost regularly from Sc to Cu.
Reason(r) : There is regular increase in i. e. across the series.
A) Both Assertion(A) and Reason(R) are true and Reason is the correct explanation for Assertion.
B) Both Assertion and Reason are true but Reason is not the correct explanation for Assertion.
C) Assertion is true but Reason is false.
D) Assertion is false but Reason is true.