A pond looks green from a distance due to the growth of algae. What could be the cause?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that a pond appears green from a distance due to the growth of algae. We need to identify the cause of this phenomenon.

2. **Identifying the Factors**: Algae growth in a pond is often influenced by various external factors, particularly human activities.

3. **Chemical Discharge**: Industries and agricultural lands surrounding the pond often discharge chemical waste into the water. This includes fertilizers, pesticides, and other pollutants.

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