The correct answer is Option 4 i.e. sin6θ.
2+tan2θ+cot2θtan2θ−sin2θ
=2+(sec2θ−1)+(cosec2θ−1)cos2θsin2θ−sin2θ
=2+sec2θ+cosec2θ−2sin2θ(cos2θ1−1)
=sec2θ+cosec2θsin2θ⋅tan2θ
=cos2θ1+sin2θ1cos2θsin4θ
=sin2θcos2θsin2θ+cos2θcos2θsin4θ
=sin2θcos2θ1cos2θsin4θ
=cos2θsin4θ×sin2θcos2θ
=sin6θ