Why is there no congruence relationship for all three angles (aaa) of a triangle? a. triangles with three identical angles are never congruent. b. to show the congruence of two triangles, only two angles at most need to be known. c. triangles with congruent corresponding angles are the same shape, but may not be the same size. d. to show the congruence of two triangles, only one angle and the length of one side, at most, need to be known.