Question

Suppose an observational study finds that American adults who participate in physical activities at least 3 times a week have a better knowledge about a healthy diet than those who don't participate in physical activities. From this study, one cannot conclude that participating in physical activities at least three times a week causes American adults to have a better knowledge about a healthy diet.

Answer 1

Agreed

Absolutely correct, One can not say about the health while participating 3 times a week