Answer:
The discovery and application Alternating Current and Direct Current on electricity generation and transmission.
Step-by-step explanation:
The development of Alternating Current and Direct Current generators allowed the possibility of installing electricity-fed street lights and lighting services to homes, made possible the existence of more compact refrigerators and revolutionized the communication by the rise of radio and television, changing the human lifestyle significantly. Allow the electrification of bigger areas, cities, states and countries.