I don't feel like the assumption in A is strictly necessary... if negated, the logic would be:

The amount of trash on the city's streets was declining at the same rate or faster before the campaign, and the campaign has still been a rousing success.

I think this can still be valid. Maybe another successful campaign directly preceded this one, so two consecutive "successful" campaigns resulted in a constant decline in trash. Or maybe something happened prior to or during the campaign that would have otherwise caused more trash to flood the streets, like a major sporting event, but the campaign maintained the previous rate of decline in trash, so it was a success. A definitely strengthens the argument, but I don't think it's logically necessary.

Why does he sound like John Mulaney in this one lol

Answer choice C seems to require a massive assumption that a manager's "effectiveness" is defined by how they extract the best performance from employees. It could be that a manager's effectiveness is defined by how well they prevent conflict in the office, how happy their employees are, etc. Seems like a slightly unreasonable assumption

"Honk some more motherfucker, see how quickly I give you the space" 😎😎😎😎

@MichaelSanantonio What adjective would you use for something that is neither well designed nor not well designed? Or neither comfortable nor uncomfortable? Theoretically those categories could exist, but I think the LSAT writers are expecting you to assume that the modifiers un- and not correspond to "/" in lawgic, i.e. they're binary. That's not necessarily something you could use a formal logic rule to determine, I think you just have to weigh the actual meaning of the words.

My CS classes are really paying off right now