It is to be noted that the Wheels are the vehicle foundation on a tractor. (Option B)
What is the wheel?
Wheels help to minimize friction. Instead of merely sliding across the ground, the wheels dig in and revolve, rotating around robust rods known as axles. Wheels offer leverage (they are examples of force multipliers or simple machines).
Wheels have the following advantages: they are less expensive, more effective in transferring power from the engine, give a smoother ride on smooth surfaces, are much quieter, can run at a greater peak speed, and take up less space.
Full Question:
Although part of your question is missing, you might be referring to this full question:
The ________________ is a vehicle's foundation?
A) Brake system
B) Wheels
C) Frame
D) Steering system