Answer:
The correct option is A.
Step-by-step explanation:
If a polynomial has n sides, then the sum of the measure of the interior angles of the polygon is
[tex]\text{Sum of interior angle}=(n-2)\times 180[/tex]
The sum of interior angles of the polygon having 9 sides is
[tex]\text{Sum of interior angle}=(9-2)\times 180=1260[/tex]
The sum of interior angles of the polygon is 1260.
The sum of exterior angles of any polygon is 360 degrees.
It means the sum of the measure of the exterior angles of the polygon having 9 sides is 360 degrees.
Therefore the correct option is A.
