The Steps Taken Toward Monetary Integration in the European Union to Create

The steps taken toward monetary integration in the European Union to create the euro included (in order)

A) increasing trade barriers, and then entering into an exchange rate mechanism where all economies fixed their currency with each other and eventually to the new currency, the euro.
B) reducing trade barriers, and then entering into an exchange rate mechanism where all economies fixed their currency with each other and eventually to the new currency, the euro.
C) entering into an exchange rate mechanism where all economies fixed their currency with the euro and then eventually to each other.
D) entering into an exchange rate mechanism where all economies fixed their currency with each other and eventually to the new currency, the euro, and then reducing trade barriers.