Consider the same wire, as shown in figure in question (iv) (a) connected in place of X. For a particular setting of rheostat, let $E_1$, $E_2$ and $E_3$ be the value of electric fields in part AC, CD and DB. Then : (A) $E_1 = E_2 = E_3$ (B) $E_3 > E_2 > E_1$ (C) $E_2 > E_3 > E_1$ (D) $E_1 > E_2 > E_3$