Total number of electrons in $\mathrm{Cu}$ atom having ${\mathrm{m}}_1= 0$:

Correct option is B)

Total number of electrons in copper are 29. The electronic configuration of Cu is 

Total number of electrons in $\mathrm{Cu}$ atom having ${\mathrm{m}}_1= 0$ is 6×2+1=13 elements.