Tropical rain forests once covering more than ….a…. Per cent of the Earth surface, now covers no more than ….b…. Per cent.

Options

A. a-30, b-19.8
B. a- 8.1, b-2.4
C. a-14, b- 6
D. a-19.8, b- 8.I

Answer

To solve the question regarding the coverage of tropical rainforests on Earth, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the percentage of Earth's surface that tropical rainforests once covered and the percentage they currently cover.

2. **Identify Historical Data**: Research or recall that tropical rainforests historically covered a significant portion of the Earth's surface.

3. **Current Coverage**: Acknowledge that due to deforestation and other environmental impacts, the area covered by tropical rainforests has decreased over time.

4. **Analyze the Options**: We have four options to choose from:
- A: 30% and 19.8%
- B: 8.1% and 2.4%
- C: 14% and 6%
- D: 19.8% and 8.1%

5. **Evaluate Each Option**:
- **Option A (30% and 19.8%)**: This is too high for both historical and current coverage.
- **Option B (8.1% and 2.4%)**: This is too low for both historical and current coverage.
- **Option C (14% and 6%)**: This aligns with known data, as tropical rainforests once covered about 14% and now cover about 6%.
- **Option D (19.8% and 8.1%)**: This is also incorrect as it does not match historical data.

6. **Select the Correct Answer**: Based on the evaluation, the correct answer is **C: 14% and 6%**.

### Final Answer:
Tropical rainforests once covered more than **14%** of the Earth's surface, and now they cover no more than **6%**.

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