What is ${\left( 2^{2} \right)^{-2}}$

${2^{ \frac{1}{4} }}$ ${\frac{1}{4}^{ 0 }}$ ${2^{ 0 }}$ ${2^{ -4 }}$ ${\frac{1}{4}^{ \frac{1}{4} }}$ ${\frac{1}{4}^{ -4 }}$