Question

today, giant pandas are at risk of becoming extinct. only about 1,000 giant pandas are left in the wild. all of these inhabit a small area in the bamboo forests of china. about 140 live in captivity. it is one of the most severely endangered species in the world.

Explanation:

The text is centered around the giant panda. The first sentence "Today, giant pandas are at risk of becoming extinct" clearly states the main idea. The following sentences provide specific numbers about the remaining wild and captive giant pandas and mention it being one of the most severely endangered species, which are supporting details.

Answer:

Topic: Giant pandas
Main Idea: Giant pandas are at risk of becoming extinct.
Supporting Details: Only about 1,000 in the wild (all in a small area of China's bamboo forests), about 140 in captivity, one of the most severely endangered species.