A

This year, the U.S. National Park Service turns 105. American's 28th President, Woodrow Wilson, formed the National Park Service in 1916 to "protect the wild and wonderful landscapes" in the United States. To celebrate its 100th birthday, the organization has been celebrating all year long in 2016. And starting on April 16, the National Park Service also celebrated National Park Week in that year.

Today, The National Park Service manages more than 400 national parks, historic sites, monuments and more, which covers nearly 34 million hectares of land. There are 127 national parks that usually charge visitors admission. Visitors to Arches National Park in Utah, for example, pay $25 per car. The Grand Canyon National Park in Arizona charges $30 per car.

But during National Park Week every year, visitors can enter all national parks across the country free of charge. National Park Week this year ran from April 16 to April 24, during which Earth Day was also celebrated, on April 22. The National Park Service urged people to volunteer at nearby national parks on that day.

In addition, to celebrate the start of National Park Week, the organization introduced some fun facts to visitors. For example, they stated "the National Park Service started 105 years ago, but some parks are more than 105 years. And Yellowstone National Park in the western United States was established in 1872 as the first national park in the America. It was also the world's first national park".

Over 300 million people visited U.S. national parks in 2020, and that was a big increase compared to 2019. Will you be one of the visitors this year?

21. What’s the main purpose to set up the National Park Service?

A. to manage the land of America

B. to celebrate the National Park Week

C. to preserve the wild and splendid landscapes in America

D. to record the fun facts about national parks

22. What were people encouraged to do on Earth Day?

A. visit the national parks free of charge      B. learn some facts about national parks

C. volunteer at nearby national parks         D. explore the history of national parks

23. What can we infer from the passage?

A. Most national parks in USA usually charge visitors admission

B. Some national parks are older than The National Park Service

C. The National Park Service manages 400 national parks now.

D. The National Park Service was celebrating from April 16 to April 24 in 2016.