Answer:
B and C
Explanation:
A linear graph, that is a graph showing a straight line connecting the points plotted, shows a proportional relationship between two variables quantities if it cuts across the point of origin at (0, 0).
Graph A represents a proportional relationship between x and y variables, because the line that connects the points on the graph is a straight line, and also intercepts at (0, 0).
Graph B is a straight line graph, however, it does not intercepts the point of origin (0, 0). Graph B cannot represent proportional relationship.
Graph C is not a linear graph. If you try connecting the points together by drawing a line, the line would not be a straight line. Also, the line of the graph does not intercept at (0, 0). Therefore, it is safe to conclude that graph C does not represent a proportional relationship.
Graph D is a straight line graph. The rate of change between any two points on the lines of both graphs would be constant and the same all through, as the line of the graph intercepts at the point of origin, (0, 0). This connotes a proportional relationship.