Question: Per Mertesacker plays as a centre back for a professional football club in HIghbury, London, England, that has won how many league titles?
Context: Arsenal Football Club is an English professional association football club based in Holloway, London.  The club was formed in Woolwich in 1886 as Royal Arsenal before it was renamed Woolwich Arsenal in 1893.  They became the first southern member admitted into the Football League in 1893, having spent their first four seasons solely participating in cup tournaments and friendlies.  The club's name was shortened to Arsenal in 1914, a year after moving to Highbury.  In spite of finishing fifth in the Second Division in 1915, Arsenal rejoined the First Division at the expense of local rivals Tottenham Hotspur when football resumed after the First World War.  Since that time, they have not fallen below the first tier of the English football league system and hold the record for the longest uninterrupted period in the top flight.  The club remained in the Football League until 1992, when its First Division was superseded as English football's top level by the newly formed Premier League, of which they were an inaugural member.  In 2003–04, Arsenal completed a league season without a single defeat, something achieved only once before in English football, by Preston North End in 1888–89. Cairnlea FC is a football (soccer) club based in Cairnlea, Victoria, Australia.  The club was formerly known as the Albion Rovers Soccer Club which was formed by the amalgamation of Royal Park Soccer Club and Albion Rovers Soccer Club in 1982.  Since this time, the club has enjoyed success playing at the highest levels in Victorian football including finals campaigns in the Victorian Premier League (VPL), a host of Victorian State League titles and many League Cups.  A combined five league titles between the Men and Women's team have given the club the most successful record of any Turkish backed club in Australian history.  Currently the club's Senior Men team play in the Victorian State League Division 2 N/W competition. Fudbalski klub Sarajevo (English: Sarajevo Football Club ) is a Bosnian professional football club based in Sarajevo, the capital city of Bosnia and Herzegovina and is one of the most successful clubs in the country.  Founded on 24 October 1946, FK Sarajevo was the most successful club from SR Bosnia in former SFR Yugoslavia, winning two Yugoslav First League titles, being runners-up on two other occasions and finishing 6th in that competition's all-time table.  The club's official colours are maroon and white.  FK Sarajevo was the only major football club founded by the post-war Yugoslav authorities in the city of Sarajevo.  The club entered the Yugoslav First League in the 1948–49 season, and eventually competed in all but two seasons in the top tier.  After Bosnia and Herzegovina gained independence from Yugoslavia, FK Sarajevo became one the country's biggest ambassadors, departing on a large world tour during the Bosnian war with the goal of gaining international support for the country's cause. The Celtic Football Club ( ) is a professional football club based in Glasgow, Scotland, which plays in the Scottish Premiership.  The club was founded in 1887 with the purpose of alleviating poverty in the immigrant Irish population in the East End of Glasgow.  They played their first match in May 1888, a friendly match against Rangers which Celtic won 5–2.  Celtic established itself within Scottish football, winning six successive league titles during the first decade of the 20th century.  The club enjoyed their greatest successes during the 1960s and 70s under Jock Stein when they won nine consecutive league titles and the European Cup. Dynamos Football Club (also referred to simply as Dynamos, or, outside of Zimbabwe, as Dynamos Harare or Zimbabwe Dynamos) is a Zimbabwean professional football club based since 1963 at Rufaro Stadium, Mbare, Harare.  The team currently participates in Zimbabwe's top-tier, the Premier Soccer League.  Founded in 1963 after a merger between two lesser teams in Mbare, Harare Township, Rhodesia, the side quickly became one of the strongest in the Rhodesian league, and by the recognition of the country's independence as Zimbabwe in 1980 had become the country's most successful team, having won six national titles.  Dynamos have won a record 22 league titles and 16 cup titles. Per Mertesacker (] ; born 29 September 1984) is a German professional footballer who plays as a centre back for Premier League club Arsenal.  He also played for the Germany national team but retired in August 2014 after winning the World Cup.  Mertesacker is a youth product of Hannover 96 and he made his senior league debut in November 2003.  He was soon dubbed "the Defence Pole" (""die Abwehrlatte"") by German tabloids and gained a reputation for his good disciplinary record, going 31 Bundesliga games without being booked.  Since joining Arsenal, their fans have nicknamed him "the BFG", which is short for "Big Fucking German" and an allusion to Roald Dahl's "The BFG" due to his height.  He has been described as an imposing, reliable, dominant and an accomplished defender. Arsenal Football Club is a professional football club based in Highbury, London, England, that plays in the Premier League, the top flight of English football.  The club has won 13 League titles, a record 13 FA Cups, two League Cups, the League Centenary Trophy, 15 FA Community Shields, one UEFA Cup Winners' Cup and one Inter-Cities Fairs Cup.  It has won the second-most top flight matches in English football history, and is the only English club to go a 38-match league season unbeaten. Seongnam FC (Korean: 성남 FC ) is a South Korean professional football club, based in Seongnam, South Korea.  Seongnam currently plays in the K League Challenge.  Founded as Ilhwa Chunma Football Club in 1989, the club is the most successful in Korean football, having won a record seven K league titles, three FA Cups, three League Cups, and two AFC Champions League titles. Richard Alan Naylor (born 28 February 1977) is an English former footballer who played as a centre back.  Naylor started his career at Ipswich Town, where he played as a striker up until he was moved to centre back by Joe Royle in 2002; he continued to play as a centre back ever since.  He has now retired from professional football and was formerly Under 18's manager of Leeds United, he also included a brief spell as Leeds' Caretaker Assistant manager after the sacking of Neil Warnock in 2013. Plymouth Argyle Football Club are an English professional association football club based in Plymouth, Devon.  They compete in Football League Two as of the 2015–16 season, the fourth division of the English football league system.  The club was formed in 1886 as Argyle Football Club, a name which was retained until 1903 when the club became professional and were elected to the Southern Football League.  The club also entered English football's premier knockout competition, the Football Association Challenge Cup, for the first time that same year.  The club joined the Football League in 1920, and have competed there since then, achieving multiple league titles, promotions and relegations.
Answer: 13