Need will mark u as brainliest
an expression is shown below:

the square root of 18 + the square root of 2

which statement is true about the expression?

a: it is rational and equal to 3
b: it is rational and equal to 4
c: it is irrational and equal to 3 times the square root of 2
d: it is irrational and equal to 4 times the square root of 2