How should your speed change when driving on wet roads?

Answer: A — Double stopping distance

When driving on wet roads, it is important to adjust your speed accordingly to avoid accidents. In this scenario, stopping distance is a critical factor to consider. Choosing options B and C to reduce speed by a third or half may not be sufficient enough when stopping on wet roads. Additionally, option D to stop immediately could result in abrupt braking and potential loss of control. Therefore, doubling your stopping distance (option A) is the most appropriate choice to ensure safe and controlled driving on wet roads.