You will have to do that via roles. It is either a single group or a single role. If you need multiple groups, you will have to add them to a custom role and then restrict the comment to that role.
Referring to the General Configuration documentation, you will only be able to set either Project Roles or Groups & Project Roles for the comment visibility options. There is no option for groups only. You may probably need to do some source codes modification to customise it if you wish to have only groups.
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