Researchers wanted to know if there is a link between proximity to high-tension wires and the rate of leukemia in children. To conduct the study, researchers compared the rate of leukemia for children who lived within 1/2 mile of high-tension wires to the rate of leukemia for children who did not live within 1/2 mile of high-tension wires. The researchers found that the rate of leukemia for children near high-tension wires was higher than the rate for those not near high-tension wires. Can the researchers conclude that proximity with high-tension wires causes leukemia in children? (This is a reading assessment question. Be certain of your answer because you only get one attempt on this question.)
A. Yes, because this is an observational studies, which allow for statements of causality.
B. No, because this is an observational study.
C. Yes, because this is a designed experiment, which allow for statements of causality.
D. No, because this is a designed experiment.

So, the answer is No, the researchers cannot conclude that proximity with high-tension wires causes leukemia in children as this is only an observational study.

Observational study is that study where the researcher observes the effect of a risk factor, diagnostic test or treatment without trying to control who is or is not exposed to it.