PIMSO 2025 - Science - Primary 6 - National Round Question 16

The set-up below is made up of four rings, P, Q, R and S. Based on the information above, which of the following are possible materials for P, Q, R and S.
I: magnet; steel; magnet; Steel
II: magnet; iron; magnet; magnet
III: iron; magnet; magnet; Plastic
IV: steel; plastic; iron; magnet



Assume the iron and steel pieces are initially unmagnetized and the support rod only guides the rings.