Question

Water bloom is caused by

• A. Bacteria
• B. Hydrilla
• C. Blue-green algae
• D. All of the above

Answer 1

Answer: (C)

The streams draining the fertilisers into the lake introduce nutrients such as nitrogen and phosphorus, which encourage the growth of algae, especially the blue green algae. As the lake's fertility increases, algal or water bloom occurs which is known as eutrophication. Algal bloom causes the deterioration of water quality and death of aquatic plants and animals like fishes.

Thus, the correct answer is option C.