What cannot be considered as a solution to urban sprawl is: c. the decreased use of public transit
Urban sprawl refers to a situation when most people start to move to the center of the cities and making it cramped.
Increasing the use of public transit actually make the matter become much worse. When this happen, the number of private vehicles that exist on the road would be increased and caused high traffic, and the number of people that can live in suburban to commute for their jobs in the cities would be limited.