What is the relationship between 'Northrop Grumman' and 'Northrop' in the context of the input sentence.
Options: headquarters location, owner of, member of, operator

As previously reported, earlier this year, Northrop Grumman announced that Kratos' C5ISR is part of the Northrop ground based strategic deterrent team, and we are looking forward to supporting Northrop, an incredible partner of Kratos’, on this critically important national security program.
owner of