Verified answer

It depends upon whether battery is connected to the capacitor or not

Case1 When battery is connect then Potential is constant and c and q thing changes

c=Ae/d so if we increase d, c will decrease

but q=cv =>v=q/c

but v=constant

so q will increase as c decrease so that v remains constant.

Case2

when battery is not connected then q will remain constant

c decrease

v increases as q=cv