When choosing your driving speed, the most important thing to consider is: ?

When choosing your driving speed, the most important thing to consider would be: the conditions of the weather, traffic, road, car, and drivers

The weather will affect the slipperiness of the road, If it's raining, it will be best if you slow down your driving speed.

Traffic, car, and road will determine a number of obstacles will you face. The more obstacles you face, the slower you should be driving 

The driver condition will affect your reflect and concentration. IF you're under the weather , it is better to drive slowly.