C & D

Hi Andrew, C does not have to be what the author believes. We know nothing about the causes of death, and this is not essential to the argument. Same for D, If life insurance holders do tend to live longer I do not see what it does to the argument.

To me C and D both eliminate the possibility that this was a biased sample. A second look at C and I see that its irrelevant but D still looks good to me because if policy holders tend to live longer than non-policy holders there may be more factors at play than just weight. Granted, that wouldn't collapse the argument, it would just be another consideration.

I think your final point is the heart of it. Sure there might be some minor relevance, but we would have to add in our own assumptions p, and either way, it isn't a necessary assumption.

Explanations please. The idea in E is that people who would lose weight would not be harmed. However, the way a person could lose weight could harm them. Amphetamine and extreme dieting could cause harm. This is why I did not choose the answer. Can you please help me to understand further.