Which one of the following statements is not valid for aerosols?

Options

A. They are harmful to human health
B. They alter rainfall and monsoon patterns
C. They cause increased agricultural productivity
D. They have negative impact on agricultural land

Explanation

To solve the question "Which one of the following statements is not valid for aerosols?", we will analyze each option provided.

### Step-by-Step Solution:

1. **Understand what aerosols are**:
- Aerosols are colloids consisting of fine solid particles or liquid droplets suspended in the air. They can originate from natural sources (like dust, sea spray) or human activities (like pollution).

2. **Evaluate each statement**:
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