Assertion: Cuprous ion $\left(C{u}^{+}\right)$  has unpaired electrons while cupric $\left(C{u}^{++}\right)$  does not.
Reason: Cuprous ion  $\left(C{u}^{+}\right)$ is colourless whereas cupric ion $\left(C{u}^{++}\right)$  is blue in the aqueous solution.
 

Assertion (A) is false and Reason (R) is true.

Assertion (A) is true and Reason (R) is false.

Both Assertion (A) and Reason (R) are the true and Reason (R) is a correct explanation of Assertion (A).

Both Assertion (A) and Reason (R) are the true but Reason (R) is not a correct explanation of Assertion (A).