The assembly pieces must be very small. The assembly process must remain exactly the same. Robots require regular maintenance. Robots must be provided with electricity.
I gave my students this multiple choice question: Robots can perform tasks that are dangerous for humans. What is the MAJOR limitation to the use of robots?

Only one answer is correct among these 4 choices:
- The assembly pieces must be very small.
- The assembly process must remain exactly the same.
- Robots require regular maintenance.
- Robots must be provided with electricity.

Could you tell me which one is correct?

The assembly process must remain exactly the same.