The correct option is B σA>σB
We know that,
E=V0d
(E=Pelectric field)
Where, V0 and d is the potential difference and perpendicular distance between two plates at the considered point.
Here, potential difference between plates at point D andF are same but distance d between plates is more at F as compared to that at D
ED>EF
σ= surface charge density
ED=σAε0
EF=σBε0
But ED>EF so,σA>σ8
Hence, option (a) is correct.