[BarTopDancer]

Thanks Alex. I understand your hesitance too. I think I understand enough to pass this assignment - it is mostly vocabulary and understanding how to interpret results.

I think A should be randomized experiment, not observational study. As I progressed through the assignment I realized I misunderstood the difference. The confounding variables are found more in randomized experiments - and this fits the situation now that I fixed it.

For the 2nd question, that is all that is provided.