Top: A fraction bar divided into 4 parts. 3 parts are shaded. Bottom: A fraction bar divided into 12 parts, 9 parts are shaded.
3
4
3 x 2
4 X 3
6
12
03
4
3 x 3
4 x 4
=
9
16
3
4
3 x 2
4x2
6
8

So don't take my word i'm not exactly a mathematical person but i would assume a. because while selling the soap every month you increase in sells so you would by 11 percent. the you would get the factor 0.89 which if i had to guess would be the monthly profit over 11 probably wrong tho