A speech introduction that begins with "Did you know that a light bulb has been invented that will last 10 times as long as the ones used today, but the government won't let it be marketed to the public?" is employing a device known as a/an

startling statement

Explanation:

Startling statement -

It refers to the piece of information added just before the starting of the speech , in order to attract the audience , is referred to as startling statement .

The method is widely used to make the speech more interesting and to introduce the audience with the subject the speaker would be talking about .

Hence , from the given scenario of the question ,

The correct answer is startling statement .

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