Use the Reset XForm (Transform) utility to push object rotation and scaling values onto the modifier stack and align object pivot points and bounding boxes with the World coordinate system. Reset XForm removes all Rotation and Scale values from selected objects and places those transforms in an XForm modifier.
To reset the transform of a group, use the Transform button in the Reset group box of the Hierarchy 
Pivot command panel.
To reset an object's transform:
Select an object.
Utilities panel, click Reset XForm.
Object rotation and scaling are now carried by an XForm modifier placed at the top of the modifier stack.
When you apply the Reset Transform utility, an XForm modifier that carries the rotation and scale values is placed at the top of the Modifier Stack display. You can apply other modifiers above and below the XForm modifier. You can select the XForm modifier and add other Move, Rotate, and Scale transforms. You can delete the XForm modifier to completely remove the transforms from the object. You can collapse the object to absorb the rotation and scale values into the object mesh.
Removes all Rotation and Scale values from selected objects and places those transforms in an XForm modifier.
