We have the equation to prepare a sandwich. The equation is balanced since the number of species in the reactants is the same as in the products. We see to make a sandwich (H2CTP5B2) we need 1 slice of cheese (C) and 2 slices of bread (B). The C to B ratio is 1/2.
Now, they give us the slices of bread =16, if we apply the ratio we can find the slices of cheese that are needed to prepare complete sandwiches.
We will need 8 slices of cheese to make as many sandwiches from 16 slices of bread.
The answer will be option b.