Groups the picked objects into a single object, allowing you to pick and apply transformations to all the components at once.
When an object is part of a group, it retains its own transformations (position, rotation and scale) but is further affected by any transformations made to the group.
Controls how null nodes (objects without geometry) are grouped:
Under – The grouped node will be grouped under the null node as a child node.
Beside – The grouped node will be grouped beside the null node as a sibling node.
Apply any transformations necessary to keep the current position of the geometry, despite any transformations applied to it by its new parents.
Turn this option off to allow geometry to adopt the transformations of any parents when it is added to a group.