If a Person has an infinite number of red, blue and yellow socks in a drawer, how many minimum socks must he pull out of the drawer to guarantee he has a pair?

If a Person has an infinite number of red, blue and yellow socks in a drawer, how many minimum socks must he pull out of the drawer to guarantee he has a pair?

4 will be the answer
in the worst case
first 3 draws will fetch u socks of different colors
R , B , Y
then the 4th socks will surely make up a pair with either of the 3 socks