Which method listed below could not be used to prove that two triangles are congruent? Why?
A Prove all three sets of corresponding sides congruent.
B Prove all three sets of corresponding angles congruent.
C Prove that two sides and an included angle of one triangle are congruent to two sides and an included angle of the other triangle.
D Prove that two angles and an included side of one triangle are congruent to two angles and an included side of the other triangle.
