Why did Japan attack China in 1937, launching the Second Sino-Japanese War?

Question

to spread Communism to other parts of Asia
to secure a buffer area against a potential Soviet attack on Japan
to secure natural resources for its growing economy and military
to retaliate after China’s attack on Japanese port cities

d?

Answer 1

https://www.google.com/search?q=Why+did+Japan+attack+China+in+1937&oq=Why+did+Japan+attack+China+in+1937&aqs=chrome..69i57j69i60.909j0j4&sourceid=chrome&ie=UTF-8

Answer 2

just a heads up the answer is indeed NOT d ^-^