Critical Reasoning

Standard aluminum soft-drink cans do not vary in the amount of aluminum that they contain. Fifty percent of the aluminum contained in a certain group (M) of standard aluminum soft-drink cans was recycled from another group (L) of used, standard aluminum soft drink cans. Since all the cans in L were recycled into cans in M and since the amount of material other than aluminum in an aluminum can is negligible, it follows that M contains twice as many cans as L.

The conclusion of the argument follows logically if which one of the following is assumed?

(A) The aluminum in the cans of M cannot be recycled further.
(B) Recycled aluminum is of poorer quality than unrecycled aluminum.
(C) All of the aluminum in an aluminum can is recovered when the can is recycled.
(D) None of the soft-drink cans in group L had been made from recycled aluminum.
(E) Aluminum soft-drink cans are more easily recycled than are soft-drink cans made from other materials.
OA is c.

why is the answer E and not A?