Answer:
B.
![18x^(2) y^(2) \sqrt[3]{3xy^(2) }](https://img.qammunity.org/2020/formulas/mathematics/middle-school/r7din4yas9sxf8ge75nd1pni5elq1qulfu.png)
Explanation:
To simplify this expression, use the fact that the root of a number (in this case is the cube root) can be expressed like a fractional exponent (1/3). Using this, the expression changes to:

Next step is to put the exponent inside the parenthesis:
Find the prime factorization of 648:
648 =3⋅3⋅3⋅3⋅2⋅2⋅2
648=3⁴∗2³

Change all improper fractions in exponent to mixed fractions

Separate integers exponents from fractional:

Re-arrange (all numbers with fractional exponents must be together):

Multiply the 3x with the numbers that have an integer exponent:

Take out the exponent 1/3 from the parenthesis:

And change the representation of the root to use a radical symbol
![18x^(2) y^(2) \sqrt[3]{3xy^(2) }](https://img.qammunity.org/2020/formulas/mathematics/middle-school/r7din4yas9sxf8ge75nd1pni5elq1qulfu.png)