C. Coordinates of D' (-6,3)
<u>Step-by-step explanation:</u>
When any figure is rotated 180° in the counterclockwise direction, then the coordinates of the vertices is changed into its opposite sign.
(x, y) → (-x, -y)
The coordinates of the vertices of quadrilateral ABCD is changed when it is rotated 180 degrees counterclockwise about the origin as,
A (7,-7) → A'(-7,7)
B (4,-10) → B' (-4,10)
C (1.5, -2.5) → C' (-1.5, 2.5)
D (6, -3) → D'(-6,3)
So the coordinates of D' will be (-6,3)
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