Among the following ,a pair of conjugate surds is

Conjugate surds : The binomial surds of the form $a+\sqrt{b},a-\sqrt{b}$  are called conjugate surds .

The sum and product of conjugate surds are rational .

The sum $=2+\sqrt{3}+2-\sqrt{3}=4$  is a rational .

The product $=\left(2+\sqrt{3}\right)\left(2-\sqrt{3}\right)=4-3=1$  is a rational .