Alunchbox contains one sandwich and one drink from the

sandwiches. drinks
cheese(c). black currant(b)
ham(h). lemonade(l)
prawn(p). water(w)

lost all possible combinations

Sandwiches = 3
Drinks = 3

1 sandwich and 1 drink.

3 × 3 = 9 

You can choose from 9 different combinations! 

Sandwiches. Drinks.
c                   b
c                   i
c                  w
h                  b 
h                  i
h                  w
p                  b
p                  i
p                  w

Cheese. Black Currant             Ham Black Currant         Prawn Lemonade

Cheese. Lemonade                  Ham Lemonade              Prawn Black Currant   

Cheese. Water                        Ham Water                     Prawn Water