Cahrges Q1 and Q2 lies inside and outside resp. of a closed surface S.Let E be the field at any point on S and @ be the flux of E over S,then which are correct options
(A) If Q1 changes,both E & @ changes
(B) If Q2 changes, E will change but @ will not change
(C) If Q1=0 and Q2 not=0 then E not=0 but @=0
(D) If Q1=not0 and Q2=0 then E =0 but @ not=0