Which of the following expressions would produce the correct alternation for the sequence

$\frac{3}{2},-\frac{7}{6},\frac{11}{24},-\frac{15}{120}$dots

Select all that apply.

Note that this question is asking about signs only.

$(-1{)}^n$

$(-1{)}^{n+1}$

$(-1{)}^{n-1}$

$-1^n$

$-1^{n+1}$

$-1^{n-1}$