Correct Option: A

There are many claimants to the title of the first company to produce practical transistor radios, often it is attributed to Sony (originally Tokyo Telecommunications Engineering Corporation). A transistor radio is a small portable radio receiver that uses transistor-based circuitry. Following their development in 1954 they became the most popular electronic communication device in history, with billions manufactured during the 1960s and 1970s. Their pocket size sparked a change in popular music listening habits, allowing people to listen to music anywhere they went.