Geometry

Question Analysis:
This question tests the ability to correctly identify when the ASA (Angle-Side-Angle) Congruence Postulate applies.
The key is recognizing when two angles and their included side are given.

Key Concept Explanation:
The ASA Congruence Postulate states that if two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the two triangles are congruent.

Step-by-Step Solution:
Evaluate each option:
Option A: Two angles (∠A, ∠B) and the included side (AB) are given → Matches ASA ✅
Option B: Two angles (∠X, ∠Y) and the included side (XY) are given → Matches ASA ✅
Option C: Two angles (∠B, ∠C) are given, but the side AC is not the included side → Not ASA ❌
Option D: Two angles (∠M, ∠N) and the included side (MN) are given → Matches ASA ✅
Confirm that ASA requires the side to be between the given angles.
Final verification: A, B, and D all satisfy ASA conditions.

Common Mistakes:
Confusing ASA with AAS. If the side is not included between the two angles, it's AAS, not ...