If the electric flux entering and leaving an enclosed surface respectively is ${\varphi }_1$ and ${\varphi }_2$, the electric charge inside the surface will be:

1. A
   $({\varphi }_2-{\varphi }_1){ϵ}_0$
2. B
   $({\varphi }_2+{\varphi }_1){ϵ}_0$
3. C
   $\frac{({\varphi }_2-{\varphi }_1)}{{ϵ}_0}$
4. D
   $\frac{({\varphi }_2+{\varphi }_1)}{{ϵ}_0}$