[tex]\bigstar\:\boxed{\bf{\purple{x^{\frac{m}{n}}}=\orange{(\sqrt[n]{x})^m}}}[/tex]
Let's solve !
[tex]:\implies\sf\:25^{\frac{3}{2}}[/tex]
[tex]:\implies\sf\:(\sqrt[2]{25})^3[/tex]
[tex]:\implies\sf\:5^3[/tex]
[tex]:\implies\boxed{\bf{\red{125}}}[/tex]
Hence, Oprion-D is correct !