Using a medium of exchange will make trade more efficent.
Explanation:
Mediums of exchange can be money or cocoa beans. They make trading easier and more efficent by making the trading process faster while also making it easier to gage the price of an object or service.
Answer 'C' = The Executive Office of the President. Consists of advisers who do not need to be approved by the U.S. Senate, although there are some staff exceptions, and provide support for the president, and respond to him.
