Answer:
C. A chart or graph
Explanation:
A timeline shows the effect of something over a period of time so if anything it would show if the percentages of people who bike, walk, ride the bus, or drive have changed over time. A map shows location so unless you want to track said students, I wouldnt use a map. And a photograph would have to be of all the students in each group place seperately to visually compare the differences. Therefore, a chart or graph is the best option, especially since it was made to show data.
