Great Britain, Denmark, and Sweden have stayed out of the euro zone because of the Multiple Choice dollar peg advocated by some members of the European Union. implied loss of national sovereignty to the European Central Bank. volatility of the euro. reluctance to compete directly against the U. S. dollar. reluctance to be considered an optimal currency area.

implied loss of national sovereignty to the European Central Bank

Explanation:

Unlike France, that has adopted the Euro as its currency, Great Britain, Denmark and Sweden have all decided to stay out of the Euro zone. This is because accepting the Euro as their currency will mean that the European Central Bank, through the Euro, has power over their economies as a result of exchange.

Also, staying away from the Euro zone means that the European central bank doesn't have control of  their monies among other things.

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