Select all choices that apply. mark each statement if it describes a way in which china's early civilization differed from other river valley civilizations. a. china's geographic location, with the gobi in the north, the himalaya to the west, and seas to the south and east, isolated early chinese civilization from other cultures. b. china's civilization began at the same time as the egyptian and sumerian civilizations. c. china's civilization is the oldest continuous civilization in the world. d. china's early civilization did not depend on channeling floodwaters.