For a binary mixture of components $A$ and $B$, $N_{A}$ and $N_{B}$ denote the total molar fluxes of components $A$ and $B$, respectively. $J_{A}$ and $J_{B}$ are the corresponding molar diffusive fluxes. Which of the following is true for the equimolar counter-diffusion in the binary mixture?

1. $N_{A}+N_{B}=0\:and\:J_{A}+J_{B}\neq 0$
2. $N_{A}+N_{B}\neq 0\:and\:J_{A}+J_{B}= 0$
3. $N_{A}+N_{B}\neq 0\:and\:J_{A}+J_{B}\neq 0$
4. $N_{A}+N_{B}= 0\:and\:J_{A}+J_{B}= 0$