Bobby earns $5 for every car he washes. which graph shows the amount bobby will earn if he washes c cars?

Here is a graph of the problem. 
You can tell because the points are (1,5),(2,10),(3,15), ect. For every Car he washes we times by 5. Example: if he's washed 10 cars, he gets $50 because 10*5=50. We model this one the graph. When the X increases by 1 the Y increases by 5.

Hnmmmn not sure