Gas was .10 cheaper in Idaho so we filled up the car there too . Our goal was to drive to Superior , MT . We got on the road at 8:30 after dinner and tried to drive the rest of the 116 miles . Immediately after Coeur D'Alene I-90 turns slow , dark , and curvy .
According to the above context, choose the best option to answer the following question.
Question: What may be the reason to get gas in Idaho ?
Options:
- We wanted to get food .
 - None of the above choices .
 - We would run out of gas before Montana .
 - The gas was cheaper .


The gas was cheaper .