Answer:
Let's solve
[tex]\qquad\quad {:}\leadsto\sf (3x^2){}^{\dfrac {2}{3}}[/tex]
[tex]\qquad\quad {:}\leadsto\sf 3x {}^{\dfrac {2×2}{3}}[/tex]
[tex]\qquad\quad {:}\leadsto\sf 3x {}^{\dfrac {4}{3}}[/tex]
[tex]\qquad\quad {:}\leadsto\displaystyle\sf \sqrt [3]{3x^4}[/tex]
Hence option b is correct
