阅读短文及文后选项，选出可以填入空白处的最佳选项。The film you see on the screen is the product of a huge amount of hard work. {#blank#}1{#/blank#}To begin with, visual special effects make scenes real. CGI （computer-generated imagery 电子成像技术）has been widely used in film-making. Mostly, scenes with CGI are filmed in front of a green screen in the studio. Green doesn't match any natural hair or skin. {#blank#}2{#/blank#} This enables CGI effects to be added later.
{#blank#}3{#/blank#} You may never expect the way that these sounds are added. For example, in Jurassic Park, the sounds of different animals were mixed by a computer. The sound of the doors opening in the Star Trek films was made by pulling a piece of paper out from an envelope.
A careful study of the background information also makes a film's success. To make his film Titanic look real, the director spent six months checking plans and then built a full-sized model ship. {#blank#}4{#/blank#} He even went down to the bottom of the Atlantic Ocean to see what was left of the ship.
The above may not include all the work behind the scenes. What we see on the cinema screen is just small parts of film-making. {#blank#}5{#/blank#}They have worked for months and even years so that you can have two hours of enjoyment!
A. Next time when watching a film, will you think about the talented people behind the scenes?
B. Do you know most of the work takes place behind the scenes?
C. He talked to historians to make sure that the details were correct.
D. Actors can be easily separated from the background by a computer.
E. Another important part of a film is sound effects.
