Utilize the input text as a context reference, choose the right relationship between 'Nexus 6P' and 'Google' from the options.
Options: operator, developer, publisher, location of formation

Google’s Nexus 6P and Nexus 5X are the first smartphones that will be sold with an Android upgrade called ”Marshmallow.” It features changes that will give Android’s personal assistant, Google Now, expanded powers to explore the information that people call up in the mobile applications.
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