<span>Segment AB is a radius of circle A. We can conclude that angle ABD is complementary to angle ABC. The answer is letter C. Complementary angles are angles that forms 90 degrees. Since the l</span>ine CD is tangent to circle A at point B and the distance of line CB is the same as that in line BD then it forms a perpendicular line at point B which divides both angle in 90 degrees.