Like other course import types, selecting a content group selects all items within the module group. However, Thin Common Cartridge content is always imported as one module, which can be extremely cumbersome in a Canvas course.
By default, content is imported as one module [1]. If you would rather import content as separate modules, click the Import sub-modules separately radio button [2].
Note: If you want to import several content groups as separate modules, module settings are applied on a per-content-group basis, meaning you must fully expand each content group and specify the separate modules option. Otherwise, all selected content in the hierarchy will always be imported as one module.