China instituted a one-child policy in 1979 because the government recognized that

China introduced the one-child policy to slow rapid population growth and reduce pressure on limited land, food, and other resources. The concern was that overpopulation would make it harder to provide for everyone, so D is correct. Being the world’s most populous country, as choice C says, is a related fact, but the policy’s underlying concern was the strain population growth could place on resources.

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