Analyzing Functions in Context

We are given graphs which relate the profit for two children selling apples, and asked to determine which graph best represents the situation.

A.	B.
C.	D.

Since the Annette and Rosalind only sell $10$ bags, the function will have a limited number of inputs. Therefore, the graph will be discrete. Moreover, since each bag is sold for $\$1$ and the price doesn't change, we expect our graph to be increasing by a constant amount. This situation is depicted in Graph A.