Many species of animal have become extinct during the last hundred years.

The correct answer is D. non-existent.

The other options are incorrect because:

• A. feeble means weak or frail.
• B. aggressive means hostile or violent.
• C. scattered means spread out over a large area.

Many species of animal have become extinct during the last hundred years. This means that they no longer exist on Earth. There are many reasons why species become extinct, including habitat loss, hunting, and climate change.