Which of the Following Would Result in a Trade Surplus

Which of the following would result in a trade surplus for the United States?

A) Exports of goods = $450 billion Imports of goods = $400 billion
Exports of services = $200 billion
Imports of services = $250 billion
B) Exports of goods = $450 billion Imports of goods = $450 billion
Exports of services = $200 billion
Imports of services = $250 billion
C) Exports of goods = $450 billion Imports of goods = $460 billion
Exports of services = $200 billion
Imports of services = $100 billion
D) Exports of goods = $450 billion Imports of goods = $490 billion
Exports of services = $200 billion