Answer:
because no nation's economy can produce all of the goods and services that it needs.
Step-by-step explanation:
Trade can be defined as a process which typically involves the buying and selling of goods and services between a producer and the customers (consumers) at a specific period of time.
Basically, nations trade because no nation's economy can produce all of the goods and services that it needs.
This ultimately implies that, country A may specialize in the production of cash crops but requires technological products too. Thus, it would purchase them from another country.