Please answer the following question: Information:  - Doraemon is a Japanese manga series written and illustrated by Fujiko F. Fujio. The series has also been adapted into a successful anime series and media franchise. The story revolves around a robotic cat named Doraemon, who travels back in time from the 22nd century to aid a pre-teen boy named .  - Doraemon : Nobita and the Birth of Japan (   Doraemon Nobita no Nippon Tanj ) is the tenth Doraemon film , which was released in 1989 . This is the first Heisei era Doraemon movie . In 2016 the movie was remade as Doraemon : Nobita and the Birth of Japan 2016  - The term "manga" (kanji: ; hiragana: ; katakana:  or ) in Japan is a word used to refer to both comics and cartooning. "Manga" as a term used outside Japan refers to comics originally published in Japan.  - The earliest commercial Japanese animation dates to 1917, and production of anime works in Japan has since continued to increase steadily. The characteristic anime art style emerged in the 1960s with the works of Osamu Tezuka and spread internationally in the late twentieth century, developing a large domestic and international audience. Anime is distributed theatrically, by television broadcasts, directly to home media, and over the Internet. It is classified into numerous genres targeting diverse broad and niche audiences.  - A media franchise is a set of related media in which several derivative works have been produced from an original creative work (usually that of fiction), such as a film, a work of literature, a television program or a video game. A media franchise is characterized by its components generally sharing a common fictional universe.     After reading the paragraphs above, we are interested in knowing the entity with which 'doraemon: nobita and the birth of japan' exhibits the relationship of 'main subject'. Find the answer from the choices below.  Choices: - anime  - art  - cat  - fiction  - film  - internet  - kanji  - literature  - television
A:
cat