Step 1: Understanding the Concept:
We need to understand the conditions for towed and self-propelled wheels.
Axle torque and pull are key parameters.
Step 2: Key Formula or Approach:
No specific formula.
Need to understand the mechanics of wheels.
Step 3: Detailed Explanation:
For a towed wheel, there is no axle torque (it is free to rotate).
So, A is correct.
For a self-propelled wheel, there is no pull (it is driven by the engine).
So, D is correct.
Thus, A and D are correct.
Step 4: Final Answer:
For towed wheel, axle torque is zero; for self-propelled wheel, pull is zero.
Hence, the correct option is (C).