Why did columbus call the people he met in america "indians"?

The natives of America, also called Native Americans, Native Americans, Native Americans, or in some American Indian countries, in a derogatory manner, are the original inhabitants of America. Under the error of Christopher Columbus, who believed they were in India, the natives were called Indians.

In most European languages, the word Indian is the same for those born in India and for Native American peoples. During the twentieth century, calling Native Americans Indians became something politically incorrect and thus a series of names emerged that were accepted and used until today: Indo-American, indigenous, Native American, Native American.

the answer is a) james madison.