Given expression is
[tex]\sqrt[4]{2}=2^{\frac{1}{4}}[/tex]
Among the given options the simplication that applies the power rule is
[tex](2^{\frac{1}{4}})^4=2^{\frac{1}{4}}.2^{\frac{1}{4}}.2^{\frac{1}{4}}.2^{\frac{1}{4}}[/tex]
This can be simplified as
[tex]2^{\frac{1}{4}+\frac{1}{4}+\frac{1}{4}+\frac{1}{4}}=2^{\frac{4}{4}}=2[/tex]
Hence the corresponding simplification is D.
