This is how I broke the question down.
Despite the relentless pursuit of fitness portrayed by media - author doesn't entirely agree that the avg population is actually pursuing the ideal of fitness all that extensively.
The average population is plumper than the average population 30 years ago - the mention of Average makes me consider scenarios where the denominator might have decreased to increase the avg. Im not certain
In 2008 the avg adult is 11 pounds heavier - a fact used to substantiate a claim made above
Question - what is the assumption made about the avg adult ( not population )
A - the author states that the avg adult is 11 pounds heavier. We have no clarity on whether the increase puts them in the "substantially" overweight category. Drop this
B - the first line of the prompt shows that the author doesn't entirely believe the media on the avg adult trying to lose weight. Drop this as well
C - no evidence to support this claim. One could gain weight for multiple reasons. A cleaner diet isn't the only factor. Drop this
D - if we were to assume that the age remains the same, then comparing efforts make a little sense. We also have the possibility that if the ages were different, the older populace would weigh more on account of not being able to effectively excersize as when younger. But if we assume that the age is lower then we can't conclude this. While tempting, i would drop as discrepancies exist
Leaves us with E - the avg populace is taller. This also isn't great for me, because if we are correlating height with increased weight, then there are obvious cases where taller adults would still weigh less. But this option has the least holes poked ,hence would go with this.
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