Whitney MacMillan (born September 25, 1929) is an American heir, businessman, philanthropist, and rancher.
 He served as the Chairman of the Board and Chief Executive Officer of his family business, Cargill, from 1976 to 1995.
Keller Williams Realty is an American international real estate franchise with headquarters in Austin, Texas.
 Founded in 1983 by Gary Keller and Joe Williams, it grew from a single office in Austin to approximately 700 offices and as of November 2016 with over 150,000 associates worldwide.
 It is the largest real estate franchise by agent count in the World, and one of the largest privately held global residential real estate brokerages.
 It is an Inc. 5000 company and has been recognized as one of the highest rated real estate companies by numerous publications, including Entrepreneur Magazine and Forbes.
ImageTrend, Incorporated is a privately held corporation based in Lakeville, Minnesota in the United States.
 ImageTrend began business in 1998, incorporating as a privately held Minnesota-based S-Corporation which develops Web-based software applications.
EnvisionTEC is a privately held global company that develops, manufactures and sells more than 40 models of 3D printers based on several distinct process technologies that build objects from digital design files.
 Founded in 2002, the company now has two corporate headquarters located in Dearborn, Mich., in Metro Detroit, and Gladbeck, Germany.
 It also has a production facility in the Greater Los Angeles area, as well as additional facilities in Montreal, for materials research, and Kiev, Ukraine, for software development.
 Today, the company's 3D Printers are used to make prototypes, tooling, production parts and finished products for a wide variety of medical, professional and industrial customers.
 EnvisionTEC has developed large customer niches in jewelry, dental, hearing aid, medical devices, biofabrication and animation.
Magnum Research Inc. (MRI) is an American privately held corporation based in Fridley, Minnesota which manufactures and distributes firearms.
 The majority owners, Jim Skildum (President and CEO) and John Risdall (Chairman, COO), have been with the company since its founding in 1979.
Radius Travel is a privately held global travel management company with headquarters in Bethesda, MD, USA.
 Radius designs and delivers travel programs for multinational companies through a network of travel agencies.
 The Radius network is made up of 100+ agencies and manages over $30 billion UDF of annual corporate travel spending.
Cargill, Inc. is an American privately held global corporation based in Minnetonka, Minnesota, a Minneapolis suburb, but incorporated in Wilmington, Delaware.
 Founded in 1865, it is now the largest privately held corporation in the United States in terms of revenue.
 If it were a public company, it would rank, as of 2015, number 15 on the Fortune 500, behind McKesson and ahead of AT&T.
Pathway Genomics is a privately held global precision medical diagnostic company with mobile applications designed to empower physicians and their patients to take control of their health and wellness.
 Based in San Diego, California, the company offers genetic testing to physicians for their patients to support treatment a variety of health conditions.
 The test menu ranges from somatic and hereditary cancer, including "BRCA1" and "BRCA2", to pharmacogenomics testing for well-known drugs like Plavix, codeine, lamotrigine, to general health and wellness testing which includes information on a number of health conditions including type 1 and type 2 diabetes and hypertension.
The Schurter Group of companies is a privately held global network of manufacturing and
Mark Walter is a founder and the chief executive officer of Guggenheim Partners, a privately held global financial services firm with more than $300 billion in assets under management and headquarters in Chicago and New York.
 He is also the Chairman of the Los Angeles Dodgers Major League Baseball franchise.

Question: Whitney MacMillan was the CEO of which privately held global corporation based in Minnetonka, Minnesota?
Answer: Cargill