题目内容：

Angry Birds has become a worldwide gaming mega hit but how did this game come into existence? Rovio is the name of the company that created angry birds, however, it's not the first game they developed. Surprisingly they have been creating games for several years but had just never broken through into the mainstream the way they did with angry birds. The idea for the game came about in 2009 when the company was looking at different ideas for games which they thought could become popular. It was a simple idea spawned from some sketches(素描) of wingless and legless birds which were angry.

The sketches caught on among the staff who in turn created a unique design which became angry birds. The pigs were added into the game later in the development as an enemy. During this period of development, pig flu was being heavily reported in the news which is where the idea for the pigs appeared.

The basis of the game is very simple and is not unique to angry birds but has been seen in many other games previously. It's a simple physics/puzzle game. The player is given a slingshot and a limited supply of angry birds with different characteristics. Some birds are faster than others while others can be split into multiple birds. You control the trajectory(轨迹) of the birds with the slingshot which launches them towards rickety structures containing your main enemy, the pigs. In order to advance to the next level you must eliminate(消灭) all of the pigs before your birds run out.

Rovio has released several different versions of the game at this point. The original, Seasons, and Rio. Seasons is a collection of holiday themed versions of the game while Rio was a movie tie in for the movie Rio. All versions continue to be updated with new levels which are free to those who have previously purchased the game.

1.What's the meaning of the underlined word in the first paragraph?

A．Turned.  B．Played a role.

C．Changed.  D．Came into being.

2.In the game, the birds ________.

A．have different kinds that only include faster birds and slower birds

B．have to be controlled to kill all of the pigs before your birds run out

C．are the enemy of the pigs which have been infected with pig flu

D．lose their temper for the pig flu so they try to kill the pigs

3.According to the text, the game players ________.

A．must pay for this game—angry birds one level by one level

B．only pay for once and then it will be updated freely

C．should control angry birds to kill all the animals with pig flu

D．will become angry easily for playing the game too much

4.Which one is the best title of the passage?

A．The Unknown Game—Angry Birds

B．Facts and Hints About the Game Angry Birds

C．Rovio Created Famous Games

D．Pigs and Angry Birds