If the net electric flux through a closed surface is zero, then we can infer
Option: 1 no net charge is enclosed by the surface.
Option: 2 uniform electric field exists within the surface.
Option: 3 electric potential varies from point to point inside the surface.
Option: 4 charge is present inside the surface.
By Gauss law
If the net electric flux through a closed surface is zero, then we can infer that no net charge is enclosed by the surface.