Icy/Snowy roads have less friction than normal roads. This means that the wheels are less likely to stay positioned because of traction, and you will spin out of control
A or possibly C because the other options have nothing to do with the size of the vibration. If i was you I would answer with A
Your rotational speed would still be the same. This is because all parts of the Ferris wheel rotate together. Your linear speed however would change. That is a function of radius. But the question is asking about rotational speed and that does not change in this situation