Help please science!

What evidence does the writer give to support his argument about coral reefs? a) he speaks of the activities of coral polyps. b) he describes the composition of the great barrier reef. c) he emphasizes the ways in which coral reefs are fragile. d) he points out the ways that scientists do research on the reefs.

What are the answers for the following questions?

Although china’s total economic output, measured by gross domestic product (gdp), is third largest in the world, it is considered a developing nation. what is most likely the most important factor for this designation? a. china’s government spends money on things that do not benefit human development. b. china has a large population, so its gdp per person is only modest. c. china has a strong economy but weak literacy and school attendance rates. d. china’s high rates of disease offset the country's economic gains.