题目内容：

Memphis Meats, a San Francisco startup company trying to create lab-grown meat from animal cells(细胞), released a video on Tuesday that shows the world’s first cultured meatball getting fried up in a pan.

“We watched how the meatball reacted in the pan, we heard the sizzle, we smelled the meat and it was exactly how you would expect a meatball to smell,” Memphis Meats chief executive Uma Valeti said in the video. “This is the first time a meatball has ever been cooked with beef cells that didn’t need a cow to be killed.”

Memphis Meats grows animal muscle tissue(组织) using stem cells of cows and pigs and feeds them oxygen and nutrients(营养物质), according to the Wall Street Journal. While there are no animals killed in making the meats, the firm does use fetal bovine serum(胎牛血清) from unborn cattle's blood to start the process.

So far, the cells grow in extremely thin layers, which is very expensive. Now it costs about $18,000 to produce a pound of Memphis Meats beef--compared to about $4 for store-bought beef.

But the company, founded by three scientists, has been experimenting growing meat from stem cells from cows, pigs, and chickens and says it’ll be selling its animal-free products to high-end customers in three to four years.

The company’s first line of products will include hot dogs, sausages, burgers and meatballs.

Valeti said in the video that his company’s process also produces 90 percent fewer greenhouse gases than traditional agriculture.

“The meat industry knows their products aren’t sustainable（可持续的）,” Valeti told the Wall Street Journal. “We believe that in 20 years, a majority of meat sold in stores will be cultured.”

It’s too early to say if we’ll all be cooking lab-grown meatballs, chicken wings, and pork chops. But for now, there is a big push to be the first to bring these foods to our plates.

1.What can be the best title for the passage?

A. Lab-grown meat is to hit the market.

B. Lab-grown meat smells as delicious.

C. Lab-grown meat is animal-free.

D. Lab-grown meat will replace traditional meat soon.

2.What’s the biggest disadvantage of the lab-grown meat?

A. It is difficult to grow.

B. It is too expensive.

C. It is difficult to be accepted by customers.

D. It doesn’t have many varieties.

3.What can we know about the lab-grown meat?

A. The layers where it grows are very expensive.

B. Cattle’s blood is needed to feed the cells.

C. Lab-grown meat has nothing to do with animals.

D. The growing process costs a lot.

4.What can we infer from the passage?

A. Lab-grown meat tastes exactly like traditional meat.

B. Traditional meat industry is not sustainable.

C. Lab-grown meat is environmentally friendly.

D. Lab-grown meat is best suitable for frying.