Information:  - Radio is the technology of using radio waves to carry information, such as sound, by systematically modulating properties of electromagnetic energy waves transmitted through space, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.  - Modern Standard Hindi (Devanagari:  , "Mnak Hind") or simply Hindi (Devanagari: , "Hind"), is an Indian language and a standardised and Sanskritised register of the Hindustani language. Hindi is one of the official languages of India, and is the "lingua franca" of the Hindi belt languages. Outside India, Hindi is an official language in Fiji, and is a recognised regional language in Mauritius, Suriname, Guyana, and Trinidad and Tobago.  - A situation comedy, or sitcom, is a genre of comedy centered on a fixed set of characters who carry over from episode to episode. Sitcoms can be contrasted with sketch comedy where a troupe may use new characters in each sketch, and stand-up comedy where a comedian tells jokes and stories to an audience. Sitcoms originated in radio, but today are found mostly on television as one9 of its dominant narrative forms. This form can also include mockumentaries.  - Nukkad (Street Corner) was the name of a popular Hindi TV serial that aired on the Indian television channel DD National in 198687. It was directed by Kundan Shah and Saeed Akhtar Mirza; it was written by Prabodh Joshi.  - Yeh Jo Hai Zindagi ( literal meaning : ' This Life As It Is ' ) is a sitcom that was popular on Indian television ; it aired for the first time in 1984 . It was written by comedy writer Sharad Joshi and directed by Kundan Shah , S. S. Oberoi and Raman Kumar . It was one of the first sitcoms and one of the biggest hit shows on Indian television after the state - owned television , Doordarshan , started sponsoring its programs .  - Kundan Shah (born 1947) is an Indian film director and writer. He is most known for his comedy classic Jaane Bhi Do Yaaro (1983) and his 19851986, TV series "Nukkad" with Saeed Akhtar Mirza.  - Sharad Joshi (Hindi  ) was a Hindi poet, writer, satirist and a dialogue and scriptwriter in Hindi films and television. He was awarded the Padma Shri in 1990.  - Sketch comedy comprises a series of short comedy scenes or vignettes, called "sketches", commonly between one and ten minutes long. Such sketches are performed by a group of comic actors or comedians, either on stage or through an audio or visual medium such as radio and television. Often sketches are first improvised by the actors and written down based on the outcome of these improv sessions; however, such improvisation is not necessarily involved in sketch comedy.  - Stand-up comedy is a comic style in which a comedian performs in front of a live audience, usually speaking directly to them. The performer is commonly known as a comic, stand-up comic, stand-up comedian, or simply a stand-up. In stand-up comedy, the comedian usually recites a grouping of humorous stories, jokes and one-liners typically called a monologue, routine, or act. Some stand-up comedians use props, music, or magic tricks to "enhance" their acts. Stand-up comedy is often performed in comedy clubs, bars and pubs, nightclubs, neo-burlesques, colleges and theatres. Outside of live performance, stand-up is often distributed commercially via television, DVD, CD and the internet.    Given the paragraphs above, decide what entity has the relation 'original network' with 'dd national'.
The answer to this question is:
yeh jo hai zindagi