The correct answer is D. Mongolia.
Explanation
The map shows part of the Asian continent including China, Mongolia, North Korea, South Korea, Taiwan, and Japan. Each one is marked with a letter of the alphabet from A to F. The letter A, corresponds to the country South Korea because it is located in the Korean peninsula, in the southern zone of South Korea is North Korea market with the letter E. Besides this, Taiwan which an island in the southern part of the Chinese coast is marked with letter B. Also, Japan is market with letter F as this is an elongated island to the east of Korea. Also, marked with C is China which is the largest country on the map. Finally to the north of China, there is Mongolia with the letter D, a country that only has borders with China to the South and Russia to the north (Not shown on the map). So, the correct answer is D. Mongolia.
