Geometry

Question Analysis:
This question tests basic recognition of the SSS Congruence Postulate when all three sides are given as congruent.

Key Concept Explanation:
SSS (Side-Side-Side) Congruence Postulate states that if three sides of one triangle are congruent to three sides of another triangle, the triangles are congruent.

Step-by-Step Solution:
List given congruent sides: AB ≅ DE, BC ≅ EF, AC ≅ DF
Count congruent pairs: All three sides match
Eliminate other options: No angle information is given

Option Analysis:
A (SAS): Requires angle between sides - not given
B (ASA): Requires two angles and included side - ...