This was considered one of the greatest technological advancements of the late 1800 s. By1880,50,000 of these were in use in the United States. By 1900, that number had increased to 1.35 million. Telegraph Telephone Television Phonograph

The correct answer is B. Telephone.<br /><br />The telephone was considered one of the greatest technological advancements of the late 1800s. By 1880, there were 50,000 telephones in use in the United States, and by 1900, that number had increased to 1.35 million. The telephone revolutionized communication by allowing people to speak to each other over long distances, making it a significant advancement in technology during that time period.