Geographical issue based on field work?

Compare demographic and environmental effects of the columbian

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.

Based on the information in the graph, what can you conclude about humans in the world in general?