Well, it is always good to have parts clean. However, it is the third option, C, that is crucial. The wheel bearing seals must be checked for the possibility of any oil leaks. This might signify one or a range of problems that will affect the safe driving of the vehicle. There should be no sign of leaks on the wheel bearing seals, not even a drop.
The seals themselves may be faulty and no mechanic worth his salt would allow a vehicle to leave the workshop with any oil leaks, let alone on the wheel bearing seals. The flow of oil must be regulated and kept within the parameters of the vehicle part assigned to the storing and transmission of oil in a regulated way.