8. researchers have found that women who take oral contraceptives (birth control pills) are at higher risk of having a heart attack or stroke than women who do not take them. they also found that the risk is substantially higher for both groups if a woman smokes. assume that the proportions of women who smoke are similar in both groups. in investigating the relationship between taking oral contraceptives (the explanatory variable) and having a heart attack or stroke (the response variable), explain whether smoking would fit the definition of each of the following: a. a confounding variable. b. an effect modifier. c. an interacting variable.

The correct answer is C.

Smoking is an interacting variable. It interacts with the birth control to increase the risk of having a heart attack or stroke rather than being the cause. It is not a confounding variable because the proportion of smokers in the two groups are the same. It is also not an effect modifier.  

diseases can be cured more rapidly as medical advancements spread from region to region. -apexxx

explanation:

daily refers to frequency, like weekly or monthly. take this medicine twice daily, once in the morning and again at bedtime. on a daily basis there refers to everyday life, to one's normal or usual behavior, activity, routine, or schedule, to the quotidien.