Critical Reasoning

Experts please comment.
Why option A is incorrect?

OA C

eitijan wrote:Why option A is incorrect?

Answer choice A is a nice trick answer set up to make you think that it explains what happened while actually it does not.

Notice what the prompt says, "the weight of glass bottles in household garbage decreased by a greater percentage than the weight of aluminum cans."

The prompt does NOT say that the weight of bottles AS A PERCENTAGE OF THE WEIGHT OF HOUSEHOLD GARBAGE declined. It conveys that the weight of bottles declined by a percentage of the weight of bottles that is greater than the percentage of the weight of cans by which the weight of cans declined.

So the fact that bottles are heavier than cans does not explain why this occurred, as to get the percentage changes the new total weight of bottles was compared only with the old total weight of bottles and the new total weight of cans was compared only with the old total weight of cans.

Once those percentage changes were calculated, THEN the percentage changes were compared with each other.