How powerful is power?

Algebra

If $\Large {\color{#3D99F6}{x}}^{\color{#3D99F6}{x}}= 2015,$ then which answer is equivalent to $\Huge \color{#3D99F6}{x^{x^{x^x}}}?$

x^{x^{2015}}

{ 2015 }^{x^x }

{ 2015 }^{ 2015 }

All the given choices are correct