The answer is 21.
This brainteaser usually involves 10 socks of each color. And, for that, the answer is three since the third sock you pull out is sure to match one of the first two socks.
But this question uses gloves, and pairs of them, which you might not have noticed if you rushed.
In the worst-case scenario, the first 10 gloves you pull out of the drawer could all be white left gloves. And the second 10 could all be black left gloves. But the 21st glove is sure to be either a white right glove or a black right glove, making a matched pair.
