Question

The current through the charged capacitor (see attachment) is given by the expression i=C dv/dt- .......... ?

Answer 1

the answer must have units of current; Amps = Coloumbs/sec

Answer 2

look at the problem as having a initial Vo and no being hooked up to a larger or smaller V because the same Vo would make "i" = 0.
answers (1) and (2) have units of voltage
answer (3) has units of energy
so now your choices are 4 or 5

Answer 3

answer 4 is farads time voltage times time which would be charge times time which is not charge per time
charge per time is current (i)

Answer 4

so 5 is the answer
is this a GRE question?

Answer 5

Good reasoning. I am inclined to agree with "the duke"