题目内容：

    Valerie Stull begins her mornings with a breakfast shake, into which she puts peanut butter, cocoa powder, banana, and milk. The last thing to go in is a powder made from insects.

Stull works at the Global Health Institute. She's in a group of researchers who study the impacts of eating insects. There's a name for dining on insects: entomophagy.

About two billion people regularly eat insects. That's almost one in every four. Most North Americans and Europeans tend to find the idea of entomophagy disgusting. Yet even in their parts of the world, insect eating is starting to catch on. That's especially true when the insects are eaten, as Stull's are, in a form that doesn't show their eyes, wings and feet.

"Some scientists view eatable insects as mini-livestock（小型牲畜）.” Compared to raising cattle and more traditional livestock, insects need far less natural resources such as land and water. Insects also are nutritious. They're packed with protein, vitamins and minerals. Plus, their outer shells contain chitin—a source of fiber.

Stull wondered if chitin and other fibers in insects might offer health benefits similar to other fibers found in a typical American diet. To find out, she teamed up with Tiffany Weir, who's a scientist at Colorado State University in Fort Collins. Breakfasts enriched with insects changed the amount of different bacteria in the gut（肠道），the two now report. And those changes were in a direction that should improve a diner's health.

These findings suggest that insects work as prebiotics（益生元）.Scientists think probiotics, which fuel the growth of helpful gut bacteria （肠道细菌），have longer and larger benefits than probiotics（益生菌）do. Probiotics exist in your gut, and you can also add them to your diet. But, Stull explains, “When you have probiotics, you're taking in a whole bunch of beneficial bacteria. But if you don't feed those beneficial bacteria, they're not going to stick around very long."

It's possible that insects offer larger benefits to people who eat them regularly. In a future study, Stull's team would like to test that idea.

1.What can we learn from the underlined sentence in paragraph 3?

A.Insect eating is one of Stull's favorite lifestyles.

B.Insect eating is quite different from entomophagy.

C.Insect eating is becoming more and more acceptable.

D.Insect eating is the most scientific way of getting nutrition.

2.what's the advantage of insect farming compared with traditional livestock farming?

A.It's face-saving. B.It's time-saving.

C.It's labor-saving. D.It's resource-saving.

3.What has Stull and Weir's study found out?

A.Insects are rich in fiber. B.Chitin is similar to other fibers.

C.Eating insects is good for health. D.Insects can keep gut bacteria in balance.

4.How do prebiotics prebioties differ from probiotics?

A.Prebiotics are good bacteria. B.Prebiotics can be added to the diet.

C.Prebiotics need to be fed regularly. D.Prebiotics can inspire good gut bacteria.