The equation c equals one third times s represents the proportional relationship between the number of bags of cement (c) and the number of bags of sand (s) required to make concrete. A graph of this relationship is shown.

Which statement is true?

The proportional relationship is graphed correctly.
The graph does not show a proportional relationship.
Bags of Sand should be on the x-axis, and Bags of Cement should be on the y-axis.
The axes are labeled correctly with the independent and dependent variables.