Breast cancer researchers found that, out of a sample of 1000 women who had been treated for breast cancer, over 60% had had a miscarriage in their lifetime. This led the researchers to conclude that there is a connection between breast cancer and miscarriages, and to encourage all women who have had miscarriages to be screened for breast cancer more frequently than women who have not had miscarriages.

Which of the following, if true, most weakens the researchers' conclusions?


A Women who have had miscarriages are also often taking birth control pills, which have a known connection to breast cancer.

B Women who have not had breast cancer also have a high rate of miscarriage after age 35.

C Women who have had previous miscarriages sometimes use fertility treatments that are thought to have connections with uterine cancer.

D In the general population, roughly 6 out of 10 women will have a miscarriage at some point in their lifetime.

E Most of the women in the study had also had at least one living child.

testguide.com