This is from the song 'Musafir Hoon Yaaron' from the 1972 film 'Parichay'. The line 'Musafir hoon yaaron...naa ghar hain naa thikaana' means 'I am a traveler, friends...neither home nor abode do I have'. This expresses the rootless wanderer's philosophy - having neither permanent home (ghar) nor temporary lodging (thikaana). The other options are incorrect: 'bus chalte jaana hain' (just keep walking) changes the theme, 'naa koi apna hain' (no one is mine) is not the lyric, and 'bus phirta rehta hoon' (just keep wandering) is not the correct completion.