The sentence that can be revised to eliminate redundacies is the last one.
The tall skyscrapers in New York City maximize the space of a small area.
The redundacy here lies on the word "tall" when refering to skyscrapers.
Skyscrapers are already tall, so you don't have to say "The tall skyscrapers."A
redundancy refers to the fact of not getting straight to the point by providing
useless information.