I'm stuck on C, please help. Thank you

Step-by-step explanation:
[tex](x {}^{4} - x) {}^{4} - ( {x}^{4} - x)[/tex]
[tex]x {}^{16} + 4( {x}^{12} ) - x + 6( {x}^{8} )( {x}^{2} ) + 4( {x}^{4} )( - {x}^{3} ) + {x}^{4} -( {x}^{4} - x)[/tex]
[tex] {x}^{16} - 4 {x}^{13} + 6 {x}^{10} - 4 {x}^{7} + {x}^{4} - {x}^{4} + x[/tex]
[tex] {x}^{16} - 4x {}^{13} + 6 {x}^{10} - 4 {x}^{7} + x[/tex]