What is the significance of the imaginary unit "i" in comple...

Question

What is the significance of the imaginary unit "i" in complex number multiplication?

A

It allows for the existence of only real solutions.

B

It represents a scalar multiple.

C

It indicates that the result will always be a negative number.

D

It represents the square root of negative one, which allows for the representation of numbers that are not on the real number line.