Self-guided travel refers to designing your own route, arranging everything on your own journey, and taking advantage of the convenience brought by modern civilization, but not unconstrained travel. According to the above definitions, Which of the following are self-guided tours:. ['The travel agency is only responsible for transportation and accommodation, and arranges sightseeing spots by itself.', 'Refer to the tour route of the travel agency, make appropriate adjustments, and drive-by yourself.', 'Tours arranged by a travel agency, but at each point, only the time is specified, and the tour route is selected by yourself.', 'Tourism organized by the unit, the tour route is designed by the travel agency, and the schedule is determined by the person in charge of the unit.']