A) the point of concurrency of the altitudes of the triangle
B) the point of concurrency of the perpendicular bisectors of the sides of the triangle
C) the point of concurrency of the bisectors of the angles of the triangle
D) the point of concurrency of the medians of the triangle
The point where the three perpendicular bisectors intersect is the circumcenter, which is the center of the circle that goes through all three vertex points of the triangle (aka circumcircle).