Which of these statements correctly expresses a similarity between ancient india and ancient china?
a. both developed democratic governments.
b. both followed the same state religion.
c. both had complex social hierarchies.
d. both offered their people social mobility.

The correct answer is C. Both had complex social hierarchies. For example, in India, this took form of the caste system.

They did not follow the same religion: India was Hindu and partially Muslim and China followed the teachings of Confucius (and those teachings included obeying the social structure).