Simplify: sqrt() 27 - sqrt() 8 + 2 sqrt() 2

a) 0
b) 3 sqrt () - 2 sqrt() 2
c) 3 sqrt () - 4 sqrt () 2
d) 3 sqrt () 3

The answer is D, because sqrt()27 simplifies to 3 sqrt()3 and negative sqrt()8 simplifies to negative 2 sqrt()2 which cancels out with the positive 2 sqrt()2.