Which of the following scientific or technological breakthroughs did not occur within the first 15 years of the 20th century?

Show Answers

Albert Einstein introduced his theory of relativityWireless signals were transmitted across the Atlantic OceanThe internet was developedThe first successful airplane was built and flownNone of the above

Explanation

Options A, B, and D all represent major scientific or technological achievements that took place between 1900 and 1915. However, the creation of the internet occurred much later, in the late 20th century, making option C the correct choice.