A research team is designing a new experiment using four materials: Material P, Material Q, Material R, and Material S.
The following conditions apply:
- Material P can only be used if Material Q is present.
- Material R cannot be used with Material Q.
- Material S must be used if Material P is not used.
Which of the following statements must be true?
I. Material P and Material R cannot be used together.
II. If Material Q is not used, Material S must be used.
III. Material P and Material S can never be used together.