Utilize the input text as a context reference, choose the right relationship between Office 365 and Microsoft from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

Microsoft added three million Office 365 subscribers during the quarter, taking the total number of paying users to 15 million.

Answer: developer