the principal square root is the positive root
(y2 means y^2, right? so if so then continue)
that means that y^2=5 and y is positive
square root means find x times x =the original number and x is the square root
you can have an example 4
square root of 4 is 2 or -2 because 2 times 2=4 and -2 times -2=4
the principal one is the positive one
the answer is D y^2=5, and y is positive
