@Kidz
The argument states that the tax codes should be changed in order to encourage savings.
But E states that, the percentage of Americans above 40 is increasing. It also goes on to state that people above the age of 40 tend to save more (they actually say that the younger part of the population doesn't save much, which in turn translates to the fact that the older generation tend to save more.). As a result of this, the savings rate of the Americans will grow. Since the savings rate is already growing, there is no point in changing the tax codes to encourage savings.
Consider this argument:
I have 4 siblings. I am the my parent's youngest child. We usually have very less food in the house, and with me being the youngest, I get the smallest portion of food. My share of food is clearly insufficient for me, so my parents should reconsider how they divide the food among my siblings and me.
Considering all the above is true, which of the following, if true, tends to weaken the argument?

E would then look like this:
My siblings will be moving out very soon.

In this case, the need to reconsider how food should be divided in our home would no longer exist. Something else is already fixing my problem.

it is a stupid example and I hope I haven't made it too complicated for you.