The situation described involves two triangles that have one pair of congruent angles between two pairs of congruent sides. This corresponds to the SAS Congruence Theorem (Side-Angle-Side Congruence Theorem), which states that if two sides of one triangle are congruent to two sides of another triangle, and the angle between those sides is also congruent, then the triangles are congruent.
Therefore, the correct response is:
the SAS Congruence Theorem