Option 1: Blooms are frequent in eutrophic lakes. This means that eutrophic lakes often experience excessive growth of algae or other aquatic plants. This is due to high nutrient levels in the water, which promote the growth of these organisms. Blooms can sometimes be harmful, as they can deplete oxygen levels in the water and disrupt the balance of the ecosystem.

Option 2: Plant nutrient flux is high. Eutrophic lakes have high levels of plant nutrients, such as nitrogen and phosphorus. These nutrients are important for the growth of algae and other aquatic plants. The high nutrient levels in eutrophic lakes can result from agricultural runoff, sewage discharge, or other human activities.

Option 3: Primary productivity is low. This is the correct answer. Eutrophic lakes actually have high levels of primary productivity, which refers to the production of organic matter by plants through photosynthesis. The excessive growth of algae and other aquatic plants in eutrophic lakes can result in high rates of primary productivity.

Option 4: Dominated by blue-green algae. Eutrophic lakes can be dominated by blue-green algae, also known as cyanobacteria. These organisms are capable of fixing atmospheric nitrogen and can thrive in environments with high nutrient levels. The dominance of