Something china and japan have in common is

Good choice:

C. was able to remain independent because France and Britain preferred that it remain so in order to serve as a buffer between their colonial territories.

Explanation:

Fortunately, the monarchy of Thailand managed to maneuver diplomatically and the Southeast Asian country managed to avoid the fate of its neighbors that fell prey of European colonialism. It managed to preserve its independence. Burma, a former British colony, is northeast of Thailand. To the west and the south lied Indochina: Laos, Cambodia, Vietnam. All of them were French colonies.