Answer:
a. greater variety and lower prices
Step-by-step explanation:
Due to the comparative advantages, countries can produce the product that they have proficiency. For example, if there are 2 countries, A and B. A have a skill of producing tasty wine, they can produce better quality of wine than B with the lower cost. When the trade barriers are reduced, the wine from A will be sold in B, the customer will have more choices of wine in the market and the price will relatively less different comparing to the price when the high barriers exist.