I would believe the answer is..
D: tire service
This is most simple and basic task. Lubrication may be easily messed up as a new technician lacks experience. Transmission and front-end work (I'm assuming this means work such as battery replacement, motor work, etc.) Secondly, when a new technician is hired at a shop they usually are under the wing of older or more experienced technicians. They are first trusted with small, basic tasks and later they are gradually given more complex tasks.
I hope this helps! Have a good day/night and don't forget to return feedback.
