The Clue ___ bus, in Mumbai
The Answer BEST
The answer to the clue "___ bus, in Mumbai" is "BEST." BEST stands for Brihanmumbai Electric Supply and Transport, which is the public bus service in Mumbai. These buses are an important part of the city's transport system, providing a convenient way for people to travel. Therefore, "BEST" fits perfectly as it directly relates to the bus service in Mumbai.