If the generator is switched on, then the lights in the hall work. If the lights in the hall work, then the function continues after sunset. It turns out that the function does not continue after sunset. Which of the following must be true?

1. A Option A: The lights in the hall work.
2. B Option B: The generator is switched on.
3. C Option C: The generator is not switched on.
4. D Option D: The generator is switched on but the lights in the hall do not work.

Answer checked 11 October 2026 · How we write and check questions