The correct answer is: C. no article, no article
In the USA, people drive on the right side of the road. This means that when you are driving, you should keep to the right side of the road. The left side of the road is for oncoming traffic.
The article “the” is used before a noun to indicate that the noun is specific or unique. In this case, there is no specific or unique right side of the road in the USA. There are many different roads in the USA, and all of them are on the right side of the road. Therefore, we do not use the article “the” before the noun “right” in this sentence.
The article “a” is used before a noun to indicate that the noun is general or indefinite. In this case, the noun “left” is not general or indefinite. It is specific and unique. There is only one left side of the road in the USA. Therefore, we do not use the article “a” before the noun “left” in this sentence.