The Price of a Bouquet of Tulips in France Is

The price of a bouquet of tulips in France is 4 euros. Jenna Algren, a frequent international traveler, found that a similar bouquet of tulips cost only 3 euros in Belgium. This demonstrates that the benefit of adopting the euro as a common currency is that it

A) makes it easier to compare prices across Europe.
B) makes Europe an optimal currency area.
C) increases the range of investment options open only to institutions.
D) leads to higher prices, which translate into substantial gains for European producers.
E) decreases competition because it has become harder for consumers to shop around.