Question: What Swiss racing driver won the 1971 Race of Champions? 

Context paragraphs:
Swiss Racing Team: Swiss Racing Team (SRT) is an auto racing team based in Inwil, Lucerne, Switzerland.  Formed by Othmar Welti and Erich Kolb in 2000, Swiss Racing Team initially competed in the German Formula Three Championship before also joining the Formula Three Euroseries from 2003 to 2004.  Frédéric Vervisch won the German Championship in 2008 earning SRT their only championship.  In 2007 the team also explored grand tourer racing, providing technical aid to Jetalliance Racing and KplusK Motorsport in the FIA GT Championship.

1951 Australian Grand Prix: It was the sixteenth Australian Grand Prix and the last to feature a handicap start which saw the slower cars starting ahead of the faster cars according to handicap allowance.  The first car over the line was the MG TC special of South Australian Steve Tillett.  The Australian Grand Prix title was however to be awarded to the driver setting the fastest outright time, regardless of handicap.  The scratch race was won by Warwick Pratley driving a George Reed built Flathead Ford V8 powered racing car.  It would be the last Australian Grand Prix victory by an Australian built car until Frank Matich won the 1971 race at the wheel of a Matich A50.  Pratley started the race ten minutes and thirty seconds behind the first car to start the race, the Morgan of Colin Uphill.  Pratley won the race by 96 seconds over the Delahaye of Dick Bland.  Both Tillett and Pratley were awarded Commonwealth Jubilee Trophies for their victories in what was effectively two races in one.

1971 Race of Champions: The 6th Race of Champions was a non-Championship motor race, run to Formula One rules, held on 21 March 1971 at Brands Hatch circuit in Kent, UK.  The race was run over 50 laps of the circuit, and was won by Clay Regazzoni in a Ferrari 312B2.

Clay Regazzoni: Gianclaudio Giuseppe Regazzoni (5 September 1939 – 15 December 2006), commonly called "Clay", was a Swiss racing driver.  He competed in Formula One races from 1970 to 1980, winning five Grands Prix.  His first win was the Italian Grand Prix at Monza in his debut season, driving for Ferrari.  He remained with the Italian team until .  After a single season with BRM, Regazzoni returned to Ferrari for a further three years, to .  After finally leaving Ferrari at the end of 1976, Regazzoni joined the Ensign and Shadow teams, before moving to Williams in , where he took the British team's first ever Grand Prix victory, the 1979 British Grand Prix at Silverstone.

Alain Menu: Alain Menu (born 9 August 1963 in Geneva) is a Swiss racing driver who is currently working for Team BMR as a driving coach.  He was one of the most successful touring car drivers of the 1990s, winning the prestigious British Touring Car Championship twice (the only driver during the series' 1991–2000 Super Touring era to do so).  He drove for Chevrolet in the World Touring Car Championship between 2005 and 2012 with a best finish of second in 2012.

Formula LO: Formula LO, previously known formally as LO Formel Lista Junior, was an open wheel racing series based in mainland Europe, which often ran as a support series to the Formula Renault 2.0 Switzerland.  The first season was in 2000 and is based in Switzerland, and governed by the country's National Motorsport Authority.  Because motorsports are essentially banned in Switzerland, the racing takes place on circuits in surrounding nations such as France, Italy and Germany.  Many of the drivers go on to race in Formula Three and especially to the closely linked Formula BMW series.  The series is often considered to be in competition with the German-based ADAC Formel Masters, which formed in 2008.  It is named after its primary sponsor, Lista Office, owned by Swiss racing driver Fredy Lienhard.

Jean-Pierre Frey: Jean-Pierre Frey (born January 6, 1955) is a former Swiss racing driver from Baselgia, Medel (Lucmagn).  He competed in full seasons of the FIA Formula 3000 Championship in 1986 and 1987 but failed to qualify for a single race in a time when the series was incredibly competitive.  Frey went to the United States to race in two CART Championship Car races in 1988 for Dick Simon Racing and two more for Euromotorsport in 1989.  He entered the 1989 Indianapolis 500 but his entry was declined due to a lack of experience.  His best CART finish was 13th place in his debut at Laguna Seca Raceway.  Frey also participated in sports car racing, including the World Sports Car Championship, the 1985 and 1988 24 Hours of Le Mans, and the 1989 24 Hours of Daytona where he drove a Zakspeed prepared Ford Probe GT-Prototype with teammates Marty Roth and Albert Naon, Jr.

Jo Siffert: Joseph Siffert (7 July 1936 – 24 October 1971) was a Swiss racing driver.

André Wicky: André Wicky (22 May 1928 – 14 May 2016) was a Swiss racing driver, active from the late 1950s to the late 1970s.  He was mainly involved in sports car racing, as an entrant and team owner as well as a driver, but also took part in several non-championship Formula One races during the 1960s.

Jo Zeller: Jo Zeller (born 17 July 1955 in Männedorf) is a Swiss racing driver.  He has raced in such series as Austria Formula 3 Cup and is a twelve-time Swiss Formula Three champion.  In the early 1990s, he set up his own racing team, Jo Zeller Racing, which has raced in series such as Formula 3 Euro Series, Formula Lista Junior, Austria Formula 3 Cup and the German Formula Three Championship.

Supporting paragraphs: 1971 Race of Champions Clay Regazzoni
Answer: Clay Regazzoni