D because without this they could not live
The trade exchanges had several positive affect on the city of Timbuktu. The city started becoming wealthy due to numerous trade exchanges. This wealth attracted many people from outside and made the city of Timbuktu very powerful. I hope that this is the answer that has come to your desired help.
Answer: specialization
Explanation:
Division of labor us simply the delegation or division of roles so that a job can be done quicker.
Opportunity cost is what is forgone by an economic entity such as an individual, firm or the government in order to get something else.
Voluntary exchange is when customers and companies engage in market transactions freely. It is the idea that people are motivated due to their self interests.
Physical capital are the consists of tangible, and the man-made objects that are purchased by a company for the production of a good.
Specialization is the concentration in a particular department or area by an individual in order to be more efficient and effective.
From the analysis, we can see that one division of labor increase, specialization increase as well.
