Correct Answer - B
Given, number of ions, i.e., `n_(1)=2.9xx10^(18)`
`n_(2)=1.2xx10^(18)`
Charge of an electron, i.e., `q=1.6xx10^(-19)C`
So,net electric current, i.e, `l=((n_(1))/(t)+(n_(2))/(t))xxq`
`= ((2.9xx10^(18))/(1)+(1.2xx10^(18))/(1))xx1.6xx10^(-19)=0.66 A`
The net electric current 0.66 towards right.