Concept:Specialization creates the need for trade, which makes money function effectively as a medium of exchange.
Explanation:When there is specialization of labour, each worker or region produces only a limited range of goods and services.
They cannot satisfy all their own wants and needs.
As a result, they must exchange their surplus output for the products of others.
This frequent exchange requires a generally accepted medium, which is money.
Money simplifies transactions and removes the difficulties of barter.
Thus, money serves better as a medium of exchange when specialization is present.
Answer:D. there is specialization of labour.