The <em>correct answer</em> is:
B) the point of concurrency of the perpendicular bisectors of the sides of the triangle
Explanation:
The definition of circumcenter is "the point of intersection of the perpendicular bisectors of a triangle."
To construct the circumcenter, we first construct the perpendicular bisector of each side of the triangle. Once we have these three lines, we find their point of intersection; this is the circumcenter.
You have to do exactly what it says calculate the length of that part of the shape.
