Final answer:
It is not possible to determine which group performed the best without more information.
Step-by-step explanation:
In a study on driving performance, it is not possible to determine which group performed the best based on the information provided. The options A, B, C, and D do not provide specific details about the groups or their performance.
If the study had provided information about the characteristics or training of each group, it would be possible to make a determination. However, without that information, we cannot say which group performed the best.
Therefore, the answer is: D) All groups performed equally.