Select the correct answer. Suppose $u=x^{3}1,$ then the indefinite integral

${\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}}{x}^2\sqrt[\phantom{2}]{x^{3}1}dx$

is equal to

$\frac{2}{9}{u}^{\frac{3}{2}}C$

$\frac{2}{9}(x^{2}1{)}^{\frac{3}{2}}C$

$\frac{2}{3}{u}^{\frac{3}{2}}C$

$\frac{2}{3}(x^{3}1{)}^{\frac{3}{2}}C$

$3u^{\frac{1}{2}}C$