Question

how can agriculture contribute to water pollution?
pesticide and fertilizer runoff
planting monocultures
too little irrigation
reduced algal blooms

Explanation:

To determine how agriculture contributes to water pollution, we analyze each option:

• "pesticide and fertilizer runoff": When it rains or there's irrigation, pesticides and fertilizers used in agriculture can be carried (runoff) into water bodies, introducing chemicals and nutrients that pollute water.
• "planting monocultures": This relates more to biodiversity loss and soil health rather than direct water pollution.
• "too little irrigation": Insufficient irrigation doesn't cause pollution; it may affect crop growth.
• "reduced algal blooms": Algal blooms are often caused by pollution (like excess nutrients), and reducing them is a result of less pollution, not a cause of pollution from agriculture.

So the correct option is the one about pesticide and fertilizer runoff.

Answer:

pesticide and fertilizer runoff