A box contains 25 bulbs. It is known that 13 of these bulbs are defective. Now I draw out one bulb from the box. This bulb is found to be defective. Now I again draw out one bulb in random from the box. What is the probability that a bulb is defective during this second draw too?

The correct option is D. $0.5$

After the first draw, it is found that one bulb is defective. Out of 25 bulbs, one bulb is drawn out. So, 24 bulbs remain in box.

It is known that initially that there were 13 defective bulbs. When one defective bulb is taken out, 12 remain.

Thus for the $2^{nd}$ draw, Number of favourable outcomes = Number of defective bulbs $=12$

Total Number of outcomes = Total number of bulbs remaining in box $=24$

Hence P(defective bulb in $2^{nd}$ draw) = $\frac{12}{24}=0.5$