Analyze the given options and select the one that corresponds to have the least percentage value.

Options

A. The percentage of drugs currently sold in the market worldwide which are derived from plants
B. The estimated percentage of total oxygen in the earth's atmosphere produced by Amazon forest through photosynthesis.
C. The percentage of tropical rain forests covering the earth's land surface presently .
D. The percentage of India share of the global species diversity

Answer

To solve the question, we need to analyze the given options and determine which one has the least percentage value. Here’s a step-by-step breakdown of the analysis:

### Step 1: Analyze the first option
- **Option A**: Percentage of drugs derived from plants.
- It is stated that approximately 25% of the medicines available in the market are derived from plants.

### Step 2: Analyze the second option
- **Option B**: Percentage of total oxygen provided by the Amazon rainforest.
- The Amazon rainforest contributes about 20% of the total oxygen on Earth.

### Step 3: Analyze the third option
- **Option C**: Percentage of Earth's surface covered by tropical rainforests.
- It was initially believed that 14% of the Earth's land area was covered by tropical rainforests, but due to deforestation, this has decreased to less than 6%. Therefore, we can consider this as approximately 6%.

### Step 4: Analyze the fourth option
- **Option D**: Percentage share of India in global species diversity.
- India has a share of 2.4% of the world’s land area but contributes 8.1% to global biodiversity.

### Step 5: Compare the percentages
- Option A: 25%
- Option B: 20%
- Option C: 6%
- Option D: 8.1%

### Step 6: Identify the least percentage
From the analysis, we can see that Option C (6%) is the least percentage value among the options provided.

### Conclusion
The correct answer is **Option C**: the percentage of Earth's surface currently covered by tropical rainforests is approximately 6%.

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