Question: Answer the following question given this paragraph: Polluted water can form a frothy green scum on the surface. This "pond scum" is actually a living organism, algae. The algae are plant-like protists. Usually the algae are too small to notice, but sometimes algae grow in excess because of the excess nutrients in polluted water. Q: What organism constitutes frothy green "pond scum"? Choices: - bacteria - sponges - protozoa - algae A:
Answer:
algae