The following statements concern the modulus. Which statement is false?

For a complex number z = a + bi, its modulus is |z| = √(a² + b²), which is always nonnegative. This formula comes from the Pythagorean theorem and gives the distance from z to the origin, so the modulus extends the idea of absolute value to the complex plane. Therefore, the false statement is that the modulus is sometimes negative.

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