San Francisco-based Fundbox, which launched in 2012 to offer working capital to business with unpaid invoices, just announced that it added Amazon CEO Jeff Bezos and early Twitter-investor Spark Capital to an investor lineup that includes Khosla Ventures and Blumberg Capital.
Take context from the input text and decide on the accurate relationship between 'Jeff Bezos' and 'Amazon' from the options provided.
Options: member of, brand, headquarters location, employer