The risk of injury increases with the total amount of physical activity. a. cardiovascular b. musculoskeletal c. cognitive d. respiratory

The correct answer here is B - the risk of musculoskeletal injury increases with the total amount of physical activity. Whilst the other forms of injury here do all relate to parts of the body involved in physical activity, it is unlikely that these injuries would occur as a direct result of exercise or strenuous physical activities if the individual in quesiton was healthy to begin with.

No because a circle or pie graph usually shows percentages you'd need a line graph