A Repair Order Came in to the City Garage for Bus

A repair order came in to the city garage for bus number 11. Melanie, one of the newer mechanics, took the order and laughed. "What?" said Geoffrey, the shop manager. Melanie said, "It's bus 11, yet again." "Let me guess," said Geoffrey. "The order says the engine is making 'weird noises.'" Melanie confirmed his assumption, and Geoffrey told her to ignore the report because nothing was wrong with the bus. Then he called over another mechanic, Raphael. Geoffrey said, "We got another 'weird noise' problem. Guess which bus?" Without pausing, Raphael replied with a smirk, "Number 11. Don't waste your time fixing it, Melanie. Nothing's wrong." Raphael then shouted out to the group of mechanics in the garage, "How many of you have tried to fix number 11's weird noises, but found nothing wrong?" Four other mechanics raised their hands. "See? Tighten the belts, and send it on its way," Raphael said to Melanie. Later that day, Melanie gave the engine a cursory look, tightened a few belts, and sent the bus back into service. The next day, bus 11 was involved in a minor accident when its brakes failed. What should Geoffrey do to prevent this type of thing from happening again?

A) He should immediately retire and disassemble all buses that come to the shop making weird noises.
B) He should formally assign Raphael the role of picking apart any assumptions that the team might make about similar problems.
C) He should limit the amount of information about busses' history that is available to the newer mechanics to reduce information overload.
D) He should demand quiet in the shop so that it is easier for the mechanics to think and communicate their ideas about the causes of problems.
E) He should give all mechanics in the shop the ability to make decisions and then ask them to cast votes on what to do in similar circumstances.