Robert constanza and his colleagues have very recently tried to put price tags on nature's life support services. They have part an average price tag of one year is :-

Options

A. US `$` 18 trillion
B. US `$` 33 trillion
C. US `$` 32 trillion
D. US `$` 16 trillion

Answer

To solve the question regarding Robert Costanza and his colleagues' valuation of nature's life support services, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Key Information**: The question mentions Robert Costanza and his colleagues attempting to put a price tag on nature's life support services. We need to find the average price tag they have assigned.

2. **Recall the Valuation**: According to the video transcript, Robert Costanza and his colleagues have estimated the average price tag for nature's life support services to be approximately **US dollar 33 trillion per year**.

3. **Compare with Global GDP**: The transcript also states that this amount (US dollar 33 trillion) is approximately **twice the gross global national product (GNP)**, which is around **US dollar 18 trillion**. This comparison helps to understand the significance of the valuation.

4. **Identify the Correct Option**: Based on the information provided, the correct answer to the question is **option number 2**, which states that the average price tag is **US dollar 33 trillion per year**.

5. **Summarize the Findings**: To conclude, the average price tag for nature's life support services, as estimated by Robert Costanza and his colleagues, is **US dollar 33 trillion per year**, which highlights the immense value of these ecosystem services.

### Final Answer:
The average price tag for nature's life support services is approximately **US dollar 33 trillion per year**.

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