When x>0, the expression
simplifies to
. The correct option is
.
Let's simplify the expression

can be simplified to 4x because the square root of 16 is 4 and
is x squared.
can be simplified as
, which further simplifies to
because the square root of 4 is 2.
Now, let's substitute these simplified forms back into the expression:

Simplifying the fraction by canceling out the common factor of 2 in the numerator and denominator gives:

This can be rewritten as
, which is equal to
.
So, when x>0, the expression
simplifies to
