UPSEE 2019 Solved Paper

As, displacement current,
Id=ε0

dϕ

dt

......(i)
Where, ϕ= electric flux
∵ ϕ=E.A
For area, A= constant
∴dϕ=AdE .......(ii)
From Eqs. (i) and (ii), we get Id=ε0A

dE

dt

So, time varying electric field generates the displacement current.
∴ Option (a) is correct.