Final answer:
The property of congruence that makes the statement true is the Symmetric Property.
Step-by-step explanation:
The correct property of congruence that makes the given statement true is the Symmetric Property.
The Symmetric Property of Congruence states that if two segments or angles are congruent, then their order can be reversed.
In this case, the given statement 'BC ≅ FG, FG ≅ BC' uses the symmetric property because it shows that segment BC is congruent to segment FG, and segment FG is congruent to segment BC.