The correct answer is Dial-up service.Dial-up service:Dial-up Internet access is a form of Internet access that uses the facilities of the public switched telephone network (PSTN) to establish a connection to an Internet service provider (ISP) by dialing a telephone number on a conventional telephone line.Dial-up connections use modems to decode audio signals into data to send to a router or computer and to encode signals from the latter two devices to send to another modem.Dial-up connections to the Internet require no additional infrastructure other than the telephone network and the modems and servers needed to make and answer the calls.Because telephone access is widely available, dial-up is often the only choice available for rural or remote areas, where broadband installations are not prevalent due to low population density and high infrastructure cost.Dial-up access may also be an alternative for users on limited budgets, as it is offered free by some ISPs, though broadband is increasingly available at lower prices in many countries due to market competition.The slowest Internet connection service is the dial-up service.Additional InformationDigital subscriber line:A digital subscriber line is a family of technologies that are used to transmit digital data over telephone lines.In telecommunications marketing, the term DSL is widely understood to mean asymmetric digital subscriber line (ADSL), the most commonly installed DSL technology, for Internet access.DSL service can be delivered simultaneously with wired telephone service on the same telephone line since DSL uses higher frequency bands for data.On the customer premises, a DSL filter on each non-DSL outlet blocks any high-frequency interference to enable simultaneous use of the voice and DSL services.The bit rate of consumer DSL services typically ranges from 256 kbit/s to over 100 Mbit/s in the direction to the customer (downstream), depending on DSL technology, line conditions, and service-level implementation. Bit rates of 1 Gbit/s have been reached.Leased Line:A leased-line is a private telecommunications circuit between two or more locations provided according to a commercial contract.It is sometimes also known as a private circuit, and as a data line in the UK.Typically, leased lines are used by businesses to connect geographically distant offices.Unlike traditional telephone lines in the public switched telephone network (PSTN) leased lines are generally not switched circuits, and therefore do not have an associated telephone number.Each side of the line is permanently connected, always active, and dedicated to the other.Leased lines can be used for telephone, Internet, or other data communication services.Some are ringdown services, and some connect to a private branch exchange (PBX) or network router.The primary factors affecting the recurring lease fees are the distance between end stations and the bandwidth of the circuit.Since the connection does not carry third-party communications, the carrier can assure a specified level of quality.Cable modem:A cable modem is a type of network bridge that provides bi-directional data communication via radio frequency channels on a hybrid fiber-coaxial (HFC), radio frequency over glass (RFoG), and coaxial cable infrastructure.Cable modems are primarily used to deliver broadband Internet access in the form of cable Internet, taking advantage of the high bandwidth of an HFC and RFoG network.They are commonly deployed in the Americas, Asia, Australia, and Europe.