Read the followingpassage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.

 Up to now, there are still many people thinking films are things that are made to be shown on screen for entertainment. It is not right. There are many other kinds of film that are made for other purposes. For example, educational films are made for school. They are about the certain subjects that students are learning. Especially, when a person who learn a foreign language, educational films in the target language are very useful. Industry needs training films which introduce about machinery and equipment, and how to operate and work on them. Documentary films present factual events and circumstances of a social, political or historical nature. It is films that help us widen our knowledge of countries, cultures and people. Sitting on the arm chair in front of a TV set, a viewer can enjoy the beauty of nature all over the world, see many historic spots, and meet a lot of interesting people. A film, either good or bad, is the result of the collaboration of many individuals with many different specific skills and talents. And we, the viewers, should choose only suitable films to enjoy.

According to the passage, all films are made ______.