Teenagers should be allowed to read whatever books they like.
Some people might argue that responsibility for the choice of what kind of writings adolescents read belongs to them. Others are sure that adults have a right to limit a variety of genres thus not hurting young readers.
As far as I am concerned, I agree that teenagers must have much more freedom in choosing a book to read. Firstly, it is important to understand that teens are not children. They are the "young adults" which are preparing for the real life.
Besides, in the modern world, TV and the Internet have a great influence on the youngsters minds. Thus, some framesthat can limit certain types of books, can not protect adolescents from the agressive impact of the external world and its technologic factors.
Nevertheless, some people are sure that the responsibility for the book selection is a paternal authority, because teenagers can not tell the difference between bad and good. As consequence, their young minds can perceive something terrible as a usually thing, or they will cease to understand the norms of the morality and spiritual values.
However, I can not agree with this point of view. I am not sure who determines what is "good" and what is "bad". The world is not divided into "black" and "white", thus everyone has a right to establish a franework of views on life, including adolescents.
To conclude, I would like to mention that a contribution of parents to the education of teenagers is very important, but it is not necessary to protect them from the difficulties of life, especially that outlined in the books.