Answer:
(D) Balance of Payments.
Step-by-step explanation:
Balance of payments accounts are the books of a country where it saves all the transactions between own country’s citizens and the rest of the world.
It includes three accounts, i.e. current account, capital account and financial accounts.
Here, following exchanges are included in Balance of Payments
Goods for goods: Like in the case, exported $500 million goods for $400 million goods
Services for goods: This happens when one country provide goods for other’s services
Services for services: Services are exchanged between two countries
Services and goods for money: Both services and goods are exchanged for money, like international projects.