False
Explanation:
Let z = x + iy, where x, y > 0
i.e. z or point A (x, y) lies in first quadrant.
Now, -iz = -I (x + iy)
= -ix – i2y
= y – ix
Now, point B (y, -x) lies in fourth quadrant.
Also ∠AOB = 90°
Thus, B is obtained by rotating A in clockwise direction about origin.