Analyze the relationship between 'Nexus 6P' and 'Google' within the context of the input sentence.
Options: location of formation, publisher, developer, operator

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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