In 1994 agreementsexisted between Canada and several countries in Europe, agreements that allowed any car authorized in one participating country to be sold in any of the others.
A. existed between Canada and several countries in Europe, agreements that allowed any car authorized in one - Correct, agreements that is noun + noun modifier that can modify anyentity.
B. had existed between Canada and several countries in Europe, agreements that allowed any car authorized in one - Wrong verb
C. existed
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A. existed between Canada and several countries in Europe, agreements that allowed any car authorized in one - Correct, agreements that is noun + noun modifier that can modify anyentity.
B. had existed between Canada and several countries in Europe, agreements that allowed any car authorized in one - Wrong verb
C. existed
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