World environment day coincides with commemoration of

Options

A. Montreal protocol
B. Vienna convention
C. First united nations conferences on human environment
D. Helsinki declaration

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks what event World Environment Day coincides with.

2. **Identify Key Dates**: World Environment Day is celebrated on June 5th every year.

3. **Research Historical Context**: The significance of June 5th relates to a major environmental conference.

4. **Locate the Relevant Conference**: The conference held from June 5 to June 16 in 1972 was the first United Nations Conference on the Human Environment, also known as the Stockholm Conference.

5. **Conclusion**: Since World Environment Day is celebrated on June 5th, it coincides with the commemoration of the First United Nations Conference on Human Environment.

6. **Final Answer**: The correct answer is C, First United Nations Conferences on Human Environment.

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