Which of the following statements about amphibians is true? A. Amphibians are represented by about 500 species of frogs, toads, and salamanders. B. Populations of amphibians in a few local areas have declined dramatically in the last few decades. C. Amphibians lay their eggs in dry, sandy areas close to a source of water. D. Their moist, absorptive skin makes amphibians very susceptible to environmental contaminants. E. Scientists increasingly perceive amphibians to be fair-weather species.