Answer:
The correct option is C.
Explanation:
It is given that Henry translates the ΔFGH to create ΔF'G'H'.
Translation is a rigid transformation. In translation, every point of the object must be moved by same distance and in the same direction.
In other words the distance between corresponding points are same.
It is given that the distance from F to F' is 4.

Since G and G' are corresponding points, so


The length of GG' is 4 centimeters.
Therefore, the correct option is C.