Which compound is not an isomer of hexane?

A.     \({\text{C}}{{\text{H}}_{\text{3}}}{\text{CH(C}}{{\text{H}}_{\text{3}}}{\text{)C}}{{\text{H}}_{\text{2}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{C}}{{\text{H}}_{\text{3}}}\)

B.     \({\text{C}}{{\text{H}}_{\text{3}}}{\text{CHCHC}}{{\text{H}}_{\text{2}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{C}}{{\text{H}}_{\text{3}}}\)

C.     \({{\text{(C}}{{\text{H}}_{\text{3}}}{\text{)}}_{\text{3}}}{\text{CC}}{{\text{H}}_{\text{2}}}{\text{C}}{{\text{H}}_{\text{3}}}\)

D.     \({\text{C}}{{\text{H}}_{\text{3}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{CH(C}}{{\text{H}}_{\text{3}}}{\text{)C}}{{\text{H}}_{\text{2}}}{\text{C}}{{\text{H}}_{\text{3}}}\)

B