(A) House parties at which numerous individuals gather to view popular television shows on one television set have increased three hundred percent during the past year.
This option has
No Impact, it explains the fact given, gives us a reason why households contains 2.73 televisions.
(B) More than one million legal immigrants enter the United States each year.
This option has
No Impact, to make it correct, we need to make an assumption that legal immigrants don't have much money to buy expensive televisions which we can't do.
(C) New devices such as video-enabled personal digital assistants and music players are increasingly purchased for use as a primary source of information and entertainment.
This
strengthens the conclusion, if new devices have such features then they can replace expensive televisions.
(D) As new technologies become more commonplace, manufacturing and retail costs normally decline.
This has
No Impact, it can't change the fact "televisions are becoming too expensive for the typical consumer", this option just gives us the trend for one type of cost.
(E) As a result of technological advances, new televisions are increasingly enabled with some features, such as Internet browsing, traditionally associated with other household devices.
This
weakens the conclusion, if new features are coming to televisions then consumers might buy expensive televisions.