Question: What Swiss agribusiness is a client of Martin Williams Advertising?

Context paragraphs:
Syngenta: Syngenta AG is a global Swiss agribusiness that produces agrochemicals and seeds.  As a biotechnology company, it conducts genomic research.  It was formed in 2000 by the merger of Novartis Agribusiness and Zeneca Agrochemicals.  s of 2014 Syngenta was the world’s largest crop chemical producer, strongest in Europe.  s of 2009 it ranked third in seeds and biotechnology sales.

The Jamaicans: The Jamaicans were a ska/rocksteady group formed in Jamaica in 1967, consisting of members Tommy Cowan, Norris Weir, Derrick Brown and Martin Williams.

Martin Williams Advertising: Martin Williams Advertising, Inc. is an advertising agency, based in Minneapolis, Minnesota.  Since 1998, Martin Williams has been part of the Omnicom Group.  Clients include Payless ShoeSource, Raymond James, Syngenta, Cargill, Marvin Windows, Simmons Bedding Company, and P.F. Chang.

Caroline Arnott: Dame Caroline Sydney Williams Arnott, DBE, OStJ, JP (born 28 December 1933) was the daughter of Sir Frederick Martin Williams, 2nd Bt., of Tregullow.

Martin Williams (diplomat): Martin Williams CVO OBE (born 3 November 1941), is a British diplomat.  He was High Commissioner to New Zealand and concurrently the Governor of the Pitcairn Islands from 1998 to 2001.  s of 2012 Williams serves as a consultant to the New Zealand Antarctic Heritage Trust.

Andreas Zivy: Andreas Zivy (born October 19, 1955) is a Swiss businessman based in Binningen, Switzerland.  He is the current chairman of Swiss agribusiness Ameropa Holding AG.

The Jazz Review: The Jazz Review was a magazine which was founded by Nat Hentoff, Martin Williams, and Hsio Wen Shih, in New York City in 1958.  It was published until 1961.  Hentoff and Williams were co-editors throughout its brief existence.

Martin Williams (politician): Martin Williams (September 25, 1858 – August 27, 1934) was an American Democratic politician who served as a member of the Virginia House of Delegates.  He was majority floor leader of the House from 1910 to 1916.

Ameropa Holding: Ameropa Holding is a Swiss agribusiness, headquartered in Binningen, Switzerland, that engages in the global distribution of fertilizers and grains.  The company was founded in 1948 by Arthur Zivy and his son, Felix Zivy.  Andreas Zivy is the chairman of the company.  It has operations in over 30 countries across all continents.

William M. Williams: William Martin Williams (September 1877 – March 30, 1932) was an American football coach.  He served as the head football coach at of the Clemson University in 1897.  Williams was a graduate of Auburn University.  He later attended Harvard University.

Supporting paragraphs: Martin Williams Advertising Syngenta
Answer: Syngenta