Comment permission by role and content type I have different roles (e.g. A, B, C) and I have different contents in a menu (e.g. A, B, C).

I want that only the user A can post/edit comments on content A,  and not on B and C.

So I don't know what module can help me with that.
What you looking for is Comment Permission module.
Some description of this module    


  The Comment Permissions module enables control of commenting by user
  role and by node type. Additional user permissions for selected node
  types are added to the user access system so you can configure
  commenting with more control than Drupal core provides.