Suppose a randomized trial estimates that a new flu vaccine is associated with a 10% reduction in absolute risk as compared to the current standard vaccine, with a 95% CI (-0.13, -0.07). Suppose you wish to present the results for the standard vaccine compared to the new vaccine. What would the 95% CI be for the risk difference be with this direction of comparison?

a. (-0.13, -0.07)

b. (0.07, 0.13)

c. (-0.13, 0.07)

d. (-0.07, 0.13)