Which of the Following Statements Is the Most Accurate Summary

Which of the following statements is the most accurate summary of the evidence linking physical activity to a reduced risk for colon cancer?

A) It is consistent across leisure time and occupational physical activity and across different study designs
B) Studies using colorectal cancer as the outcome measure have consistently found a strong, inverse link between level of physical activity and risk
C) Occupational, but not leisure-time, physical activity is inversely associated with risk of colon cancer
D) The inverse relationship between physical activity and risk for colon cancer is eliminated after controlling for known confounders