Hello. You have not presented the chart to which this question refers, which makes it impossible for it to be answered. However, I will try to help you as best I can.
A bar graph is used to show a comparison between the amount or intensity of different elements. An example bar graph is attached so you can better understand how it works. In this case, to answer your question, you need to compare the size of the bars of the graph presented by that question.
Each bar corresponds to the number of miles Amy ran each day of the week. If the smallest bar is the Friday bar, the letter A is your answer, because it shows that Amy runs fewer miles on Friday, this could be because she doesn't like to run that day. If there are no bars on Tuesday, it means the letter D is your answer, because Amy doesn't run any mile on Tuesday. If the longest bar is on Thursday, the letter C is your answer, as it shows that Amy runs more miles on Thursday. If none of these cases apply, your answer is the letter B.