题目内容：

A 90-year-old may not be typical for a show's narrator（解说员）,but without the voice of English broadcaster Sir David Attenborough,one of the most successful new shows on television just wouldn't be the same.

BBC's Planet EarthⅡis getting good ratings in the United Kingdom.And Sir David,the man behind the show's voice,describes it as "greatly pleasing".The naturalist is the father of nature documentaries（纪录片）,with a television career that started in 1950.Since then,the London-born broadcaster has traveled the world intent on sharing his discoveries through the television in new ways.

Ever since his first wildlife documentary series,1954's Zoo Quest,Sir David's voice has become synonymous（同义）with environmental protection.Concerned with how humans are harming the planet,he attempts to educate viewers on the threats and dangers that are present today.He's used his profile to raise important issues like global warming,deforestation,climate change and overpopulation.

"We can't go on increasing at the rate human beings are increasing forever,because the Earth is finite（有限）and you can't put infinity into something that is finite,"he told The Independent two years ago."So if we don't do something about it then the world will do something about it."

And after almost 30 years of nature-based programming,Sir David's efforts to protect wildlife and the environment have not gone unnoticed.His work has been significant in reconnecting an increasingly disconnected human population with the environment of the planet that we not only come from but also rely on.

1.What can we learn about Planet EarthⅡ?

A. It was made in 1950.

B. It is now very popular.

C. It is broadcast all over the world.

D. It was filmed in the United Kingdom.

2.When did Sir David's job begin to be widely recognized?

A. In 1950.

B. In 1954.

C. When he is 90 years old.

D. After 30 years of hard work.

3.What does Sir David intend to tell in Paragraph 4?

A. We will lose control of the worsening of the Earth.

B. He will help to deal with some important issues.

C. Measures should be taken to protect the Earth.

D. Human population should stop increasing.

4.Which of the following best describes Sir David according to the text?

A. Optimistic.    B. Ambitious.

C. Generous.    D. Devoted.