A variable, opposite external potential $(E_{ext})$ is applied to the cell $Zn|Zn^{2+} \; (1M) || Cu^{2+} \; (1M) | Cu$, of potential $1.1\;V$. When $E_{ext} < 1.1\;V$ and $E_{ext} > 1.1 \;V$, respectively electrons flow from :

Question

( A ) cathode to anode in both cases
( B ) anode to cathode and cathode to anode
( C ) cathode to anode and anode to cathode
( D ) anode to cathode in both cases