Traffic Court Options, Arraignment or Court Trial ?

I got a traffic ticket and received courtesy notice from court today. There are 2 options under Request Court Appearance, Arraignment and Court Trial. Which one should I choose?

Here was my scenario when I got the ticket. On highway service road exit, the car in front of me did not try merge to highway lane untill the line almost became solid. Since he was not able to merge, he stopped in the lane. So, I drove around him by crossing the right shoulder. Cop said I should stop behind him, and I should not make a unsafe pass. I want to argue that I was trying to aviod an accident, if I tried to stop, the car behind me might hit me.