A diplomatic representative of one country in another is known as:

The question asks for the term describing a diplomatic representative of one country in another. This role involves representing one's nation and its interests in a foreign state.

• The correct answer is Ambassador. An ambassador is the highest-ranking diplomatic representative sent by one country as its permanent representative in another.
• Arbitrator is incorrect because an arbitrator is an independent person appointed to settle a dispute, not a diplomatic representative.
• Antagonist is incorrect as it means an opponent or adversary, which is the opposite of a diplomatic role.
• Aristocrat is incorrect because it refers to a member of a ruling class, not a specific diplomatic function.