Answer:
Mikhail Sergeyevich Gorbachev[e] (born 2 March 1931) is a Russian and former Soviet politician. The eighth and last leader of the Soviet Union, he was the General Secretary of the Communist Party of the Soviet Union from 1985 until 1991. He was also the country's head of state from 1988 until 1991, serving as the chairman of the Presidium of the Supreme Soviet from 1988 to 1989, chairman of the Supreme Soviet from 1989 to 1990, and president of the Soviet Union from 1990 to 1991. Ideologically, Gorbachev initially adhered to Marxism–Leninism, although he had moved towards social democracy by the early 1990s.
The answer is of course B - water.
Japan is consisted out of four big islands (Honshu, Hokkaido, Shikoku, and Kyushu). While each of them also has their own small characteristics, separate from each other, Japan has in general been isolated due to its specific geographical environment. Not being connected to any landmass such as neighbouring China, the only contact they could have had was by boat. And travelling by boat has always been more difficult compared to packing your stuff and going somewhere.
Lack of mineral resources has forced Japan to become a trading nation.
