All of these are advantages to having states share a common market except that trade outside of the country is prohibited.
Answer: Option B
Step-by-step explanation:
Establishing a common market shared by all the States in a country is a very progressive step for boosting the overall economy of the country. Common market will help to create a single national economy for the country.
It will also help the good and resources to move free from one part of the country to another without any access fee or taxes. It is essentially a good incentive for establishing large business in different States. Hence, we can save common market will over all push the economy upwards.