The boolean expression for the shaded regions as shown in the figure is _________
- $(A+B)\bullet (\overline{A}+\overline{B})$
- $(A+\overline{B})\bullet (\overline{A}+B)$
- $(\overline{A}+B)\bullet (\overline{A}+\overline{B})$
- $(\overline{A}+\overline{B})\bullet (A+\overline{B})$