ANS:A - D₁ forward and D₂ reverse

 consider at time T0: voltage V out is undefined. If we assume that voltage to be less than the anode vg of the diode D1 then and then only it is said to forward biased. Same thing to the diode D2 and hence anode voltage at D2 is 0v and hence which is less than the previous assumption the it is reverse biased. (if you assume in opposite way then both of the diodes are reverse biased).