If the rate ratio (rr) and its 95% confidence interval for a cohort study is rr = 1.1 (0.7, 1.6), what is the most appropriate conclusion about the association between the exposure and the disease of interest?
a. the exposure is a risk factor for the disease
b. there is no statistically significant association between the exposure and the disease
c. the exposure is protective against the disease.
d. none of these