Question

what was not a significant technological development of the postwar era?
television
computers
radio
transistors

Explanation:

Radio was already well - established before the postwar era. Television became popular in the postwar era as a new form of home entertainment. Computers had significant developments in the postwar era with the transition from large mainframes to more accessible forms. Transistors were a key technological advancement in the postwar era, replacing vacuum tubes in electronics.

Answer:

radio