SOLUTION

Reverse biasing means, applying an external voltage that is opposite in direction to forward bias i.e connecting the positive terminal of the battery to the n-side of the diode and the negative terminal of the battery to the p-side of the diode.

Under reverse bias, the diode does not conduct when the applied voltage is changed. The current remains constant at a negligibly small value (in the range of microamps) for a long-range of change in applied voltage.