Nuclear Density Comparison

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : The density of the copper $\left( {_{29}^{64}Cu} \right)$ nucleus is greater than that of the carbon $\left( {_{{\text { }}6}^{12}C} \right)$ nucleus.
Reason (R) : The nucleus of mass number A has a radius proportional to A^1/3.
In the light of the above statements, choose the most appropriate answer from the options given below :

SELECT ONE OPTION