Find the incorrect statement .

Options

A. Sixth extinction' is different from previous extinction terms of rate of extinction.
B. Ecologists warn that if the present trend of extinction continues , nearly 50 percent of all species on earth might be wiped out within the next 100 years.
C. Amphibians appear to be more vulnerable to extinction.
D. Recent extinction is completely natural.

Answer

To find the incorrect statement regarding the 6th extinction, we will analyze each statement provided in the question step by step.

### Step 1: Analyze the First Statement
**Statement:** The 6th extinction is different in terms of rate from other extinctions.

**Analysis:** This statement is correct. The current rate of extinction due to human activities is significantly higher than the rates observed during previous mass extinction events. The 6th extinction is characterized by a rapid loss of biodiversity, primarily driven by human actions.

### Step 2: Analyze the Second Statement
**Statement:** Ecologists say that if the current trend of extinction continues, then in the next 100 years, 50% of the Earth's biodiversity can be wiped out.

**Analysis:** This statement is also correct. Many scientists and ecologists have predicted that if current trends in biodiversity loss continue, a significant portion of Earth's species could face extinction within the next century.

### Step 3: Analyze the Third Statement
**Statement:** Amphibians are more vulnerable to extinction.

**Analysis:** This statement is correct as well. Amphibians are indeed among the most vulnerable groups due to their dependence on both terrestrial and aquatic habitats, making them particularly susceptible to habitat destruction and environmental changes.

### Step 4: Analyze the Fourth Statement
**Statement:** The recent extinction, the 6th episode, is completely natural.

**Analysis:** This statement is incorrect. The current extinction event is primarily driven by human activities, such as habitat destruction, pollution, and overexploitation of species. Unlike previous mass extinctions that were caused by natural events, the 6th extinction is largely anthropogenic.

### Conclusion
The incorrect statement is the fourth one, which claims that the recent extinction is completely natural.

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