Correct answer: (c) Japan
Explanation
- A
North Korea
(a) North Korea. The Korean peninsula has other plains; Nobi and Kanto are not North Korean.
- B
South Korea
(b) South Korea. South Korea’s coastal plains are not the Nobi–Kanto pair.
- C
Japan
(c) Japan. The Kanto plain is the Tokyo–Yokohama lowland on Honshu; the Nobi plain is the Nagoya lowland around Ise Bay. Both are Japanese alluvial plains. That country is the official key.
- D
China
(d) China. China has the North China and Yangtze plains, not Nobi and Kanto.
Summary. Official key is (c) Japan. Kanto is Japan’s largest plain and the demographic core around Tokyo. Nobi (Nōbi) centres on Nagoya in the Chubu region. Neighbouring Japanese plains include the Kinai/Osaka plain. Korean and Chinese options are distractors from East Asian geography lists.