Geometry

Question Analysis:
This question involves using vertical angles to apply the SAS Congruence Postulate.
The main focus is recognizing that vertical angles are always equal, which provides the included angle needed for SAS.

Key Concept Explanation:
SAS Congruence Postulate: If two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, the triangles are congruent.

Step-by-Step Solution:
Identify Given Information:
AB = DE ✅ (corresponding sides)
BC = EF ✅ (corresponding sides)
∠ABC = ∠DEF ✅ (vertical angles are always congruent)
Check for SAS Conditions:
Two pairs of corresponding sides are equal. ✅
The included angle (between these sides) is also equal. ✅
This satisfies SAS, proving △ABC ≅ △DEF. ✅

Option Analysis:
(A) Correct: The given sides and included angle satisfy SAS, proving congruence. ✅
(B) Incorrect: ASA requires two angles and a side, but we have two sides and an angle. ❌
(C) Incorrect: The trian...