The four main islands of japan are
a. hiroshima, honshu, jomon, and kyushu
b. honshu, nagasaki, mandala and shikoku
c. genji, hiroshima, jomon, and honshu
d. hokkaido, honshu, shikoku, and kyushu

The correct answer is - d. Hokkaido, Honshu, Shikoku, and Kyushu.

Japan is an island country, consisted of multiple islands, some small, some big. The four biggest are Honshu, Hokkaido, Kyushu, and Shikoku.

The biggest and most populated Japanese island is Honshu. It is the island on which the biggest cities are located, and it is in between the other three main islands. The second biggest, but the least populated, is the island of Hokkaido, located in the northern part. Kyushu is the third by size, and it is located on the southern part, while Shikoku is the smallest of the four, being located south of the southern tip of Honshu.