Irrelevant. We don’t care about general trash and how it compares to the cost of recycling. We're interested in how this new recycling program will compare to the old recycling program.

This doesn't weaken the editor's argument. This claim is certainly consistent with the editor's position that the city's new program won't live up to the city's claims. But this statement actually doesn't weaken the city's claim, either. The city never claimed the new program would be "cost-effective" in general, whatever standard that would be based on — the city just claimed that the new program would be "more cost-effective" than the old one. So this answer choice is irrelevant.

Even if each pickup takes less time, there will be twice as many pickups as before. Since we don't know how the time spent on each pickup versus the total number of pickups affects cost efficiency, we can't say this undermines the editor's argument. If having more frequent pickups, even if they are shorter, is more expensive overall, or if the two changes balance out to the same cost as before, then this answer choice could be perfectly consistent with the editor's claim that the new program will not be more cost-efficient than the old one.

This weakens the editor's argument. It suggests that the editor might not be right in claiming that the overall volume of recycling will stay the same. People might put out more recyclables because they remember the weekly schedule better. This scenario would strengthen the city's argument and undermine the editor's.

This strengthens the editor’s argument that the new program will not be more cost-effective. The contractor charging more to collect recyclables might outweigh whatever benefit, if any, comes from collecting recyclables more frequently.