The answer is b. demand for cotton grew after W.W.1
The reunification of Japan is accomplished by three strong daimyo who succeed each other: Oda Nobunaga (1543-1582), Toyotomi Hideyoshi (1536-1598), and finally Tokugawa Ieyasu (1542-1616) who establishes the Tokugawa Shogunate, that governs for more than 250 years, following the Battle of Sekigahara in 1600.
Answer: They claimed Mexico and conquered the Aztec empire!