Dr Rhee Conducted a Study in Which She Assessed Preventive

Dr. Rhee conducted a study in which she assessed preventive health practices of two cohorts (1940 and 1950) at two different ages (60 and 70) . Dr. Rhee examined her results and concluded with confidence that changes in preventive health practices were part of the normal aging process. What must Dr. Rhee have observed in her data?

A) significant differences between the two cohorts but no significant differences between the two ages
B) significant differences between the two cohorts and significant differences between the two ages
C) no significant differences between the two cohorts and no significant differences between the two ages, but a significant interaction between cohort and age
D) no significant differences between the two cohorts and significant differences between the two ages