2. you should only pass on a two-way road when
a. the oncoming vehicle is at least 3-4 seconds away
b. the oncoming vehicle is at least 8-10 seconds away
c. the oncoming vehicle is at least 10-12 seconds away
d. you should never pass if there is an oncoming vehicle

C. The oncoming vehicle is at least 10-12 seconds away  

Explanation:

Regardless of whether the race is two-way or one-way, you should always drive to ensure your safety and the safety of others on the road. To drive safely, you must obey all traffic laws and regulations as well, such as signs that indicate what can and cannot be done on the road. Among these rules, it is important to abide by the one when you should go on a two-way road. The correct thing is that in this situation you should only pass when the approaching vehicle is at least 10-12 seconds away.

51% were unhappy, i think .   ; )