Question: Alan Dunbar (born 30 April 1990) is a Northern Irish professional golfer who won the 2012 Amateur Championship at Royal Troon, His home club is Rathmore Golf Club near Portrush, in which county that's one of six counties that form Northern Ireland?

Context paragraphs:
1997 Open Championship: The 1997 Open Championship was a men's major golf championship and the 126th Open Championship, held from 17–20 July at the Royal Troon Golf Club in Troon, Scotland.  Justin Leonard won his only major championship and was the fifth consecutive American to win at Royal Troon.

1982 Open Championship: The 1982 Open Championship was a men's major golf championship and the 111th Open Championship, held from 15–18 July at Royal Troon Golf Club in Troon, Scotland.  Tom Watson won his fourth Open Championship, one stroke ahead of runners-up Peter Oosterhuis and Nick Price.  It was Watson's second consecutive major victory; he won the U.S. Open a month earlier, and the seventh of his eight major titles.

Royal Ascot Golf Club: The Ascot Golf Club was founded in 1887 .  It is the second oldest and the only Royal Golf Club in Berkshire.Originally golf was played on Ascot Heath within the confines of the Race Course and became a Royal Club by Royal Command of Queen Victoria in 1887.  Hamilton was the president of this club \.  The course was designed by J.H.Taylor who went on to design many courses in Europe.  One of the earlier competitions was The Boys Amateur Championship which was played on The Heath in1921.  The Trophy for this was presented to The Royal and Ancient Golf Club and is still played for annually.  An early competitor in this tournament was a young Henry Cotton later to become Sir Henry.After all the years The Club had played on The Heath, it came as a great shock to receive a notice from The Ascot Authority on the 13 November 2000 to vacate The Heath.  At this time it was a thriving Club with a waiting list for members and a very active social life.  The Committee at the time decided to try to find an alternative location in discussions with The Authority but no progress could be made.The problem was that The Club had no formal lease or agreement.  The Chairman wrote to The Queen and an immediate response was forthcoming.  Land was offered to the Club on the other side of the road in Sunninghill Park and plans to resite The Club started in earnest.  Eventually the new Clubhouse opened in December 2004 but golf continued on The Heath until August 2005. Thanks to the efforts of a few there is still a Golf Club today.  The New Clubhouse was opened by HRH Duke of York The Patron of The Club on23 May 2006 . The New course is ranked as the 18th best golf course in the county by the website Top 100 Golf Courses.

2016 Open Championship: The 2016 Open Championship was a men's major golf championship and the 145th Open Championship, played from 14–17 July at Royal Troon Golf Club in Ayrshire, Scotland.  It was the ninth Open Championship played at the Old Course of Troon, and the fifth since gaining royal status.

1950 Open Championship: The 1950 Open Championship was the 79th Open Championship, held 5–7 July at Troon Golf Club in Troon, South Ayrshire, Scotland.  Defending champion Bobby Locke of South Africa won the second of his four Open titles, two strokes ahead of runner-up Roberto De Vicenzo of Argentina.  His total of 279 was a record for the Open Championship, beating the previous best of 283.  It was the second Open Championship at Troon, which had previously hosted the Championship in 1923; it became "Royal Troon" in 1978.

Leaderboard Golf Ltd: Leaderboard Golf Ltd is a company that owns four renowned Golf Clubs in South East England, including The Oxfordshire Golf Club near Oxford, Sandford Springs Golf Club near Basingstoke and Newbury, Dale Hill Hotel and Golf Club near Tonbridge and Royal Tunbridge Wells and Chart Hills Golf Club near Ashford in Kent.

County Antrim: County Antrim (named after the town of Antrim, from Irish: "Aontroim" , meaning "lone ridge" , )) is one of six counties that form Northern Ireland.  Adjoined to the north-east shore of Lough Neagh, the county covers an area of 3046 km2 and has a population of about 618,000.  County Antrim has a population density of 203 people per square kilometer / 526 people per square mile.  It is also one of the thirty-two traditional counties of Ireland, as well as part of the historic province of Ulster.

Alan Dunbar: Alan Dunbar (born 30 April 1990) is a Northern Irish professional golfer who won the 2012 Amateur Championship at Royal Troon.  His home club is Rathmore Golf Club near Portrush, County Antrim.

2004 Open Championship: The 2004 Open Championship was a men's major golf championship and the 133rd Open Championship, held from 15–18 July at the Old Course of Royal Troon Golf Club in Troon, Scotland.

1989 Open Championship: The 1989 Open Championship was a men's major golf championship and the 118th Open Championship, held from 20–23 July at the Royal Troon Golf Club in Troon, Scotland.  Mark Calcavecchia won his only major championship in a playoff over Greg Norman and Wayne Grady.  It was the first playoff at the Open in fourteen years and the first use off the four-hole aggregate playoff, adopted in 1985.  The playoff was formerly 18 holes the following day (and 36 holes prior to 1964).  Calcavecchia was the first American champion at The Open in six years.  Norman shot a course record 64 (−8) in the final round to get into the playoff.

Supporting paragraphs: Alan Dunbar County Antrim
Answer: County Antrim