Which one of the four shown diode circuits is forward biased?

Question

G1 Physics · Accepted Answer

For a silicon diode to conduct in forward bias, the anode (p-side) must be at a higher potential than the cathode (n-side), by approximately 0.7 V for appreciable conduction. Compare terminal potentials and diode orientation in each source circuit; Circuit D satisfies the forward-polarity condition. Final answer: Option D.