Interactive Reading

Read the passage and answer the question.

Tardigrades, often called water bears, are microscopic animals famous for surviving conditions that would kill almost anything else. When their environment dries out, they curl into a tiny ball and nearly stop their metabolism, entering a state in which they can endure extreme heat, freezing cold, and even the vacuum of space. In this dormant form they have lasted for decades without water. Yet their reputation for toughness can be misleading. Tardigrades are only this resilient while dormant; when active and hydrated, they are surprisingly fragile and can be harmed by ordinary stresses. Their survival trick is not strength, but the ability to pause life almost completely.