Verified Answer :

the answer is trade deficits.

All of
these restrict international trade except trade deficits.

 

Trade deficit is an
economic measure of a negative balance of 
trade in
which a country's imports exceeds its exports. A 
trade deficit represents
an outflow of domestic currency to foreign markets

 

The correct answer between all
the choices given is the last choice or letter D. I am hoping that this answer
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