The following Boolean expression:

$Y=\frac{A}{b}ar\frac{B}{b}ar\frac{C}{b}ar(D)\frac{+}{b}ar(A)\frac{B}{b}ar(C)D\frac{+}{b}ar\frac{A}{b}ar\frac{B}{b}ar(C)D$

$\frac{+}{b}ar\frac{A}{b}ar(B)CD+\frac{A}{b}ar\frac{B}{b}ar(C)D$

can be simplified to:

$($A$)\frac{?}{\text{b}\text{a}\text{r}}\frac{A}{b}ar(B)C+\frac{A}{b}ar(D)$

$($B$)\frac{?}{\text{b}\text{a}\text{r}}(A)\frac{B}{b}ar(C)+\frac{A}{b}ar(D)$

$($C$)A\frac{*}{b}ar\frac{B}{b}ar(C)\frac{+}{b}ar(A)D$

$($D$)\frac{A}{b}ar(B)C\frac{+}{b}ar(A)D$