Question: Per Mertesacker plays as a centre back for a professional football club in HIghbury, London, England, that has won how many league titles?

<P0-S0> 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. <P0-S1>  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. <P0-S2>  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. <SEP> <P1-S0> Richard Alan Naylor (born 28 February 1977) is an English former footballer who played as a centre back. <P1-S1>  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. <P1-S2>  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. <SEP> <P2-S0> Arsenal Football Club is an English professional association football club based in Holloway, London. <P2-S1>  The club was formed in Woolwich in 1886 as Royal Arsenal before it was renamed Woolwich Arsenal in 1893. <P2-S2>  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. <P2-S3>  The club's name was shortened to Arsenal in 1914, a year after moving to Highbury. <P2-S4>  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. <P2-S5>  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. <P2-S6>  The club remained in the Football League until 1992, when its First Division was superseded as English football's top level by the newly formed Premier League, of which they were an inaugural member. <P2-S7>  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. <SEP> <P3-S0>  He also played for the Germany national team but retired in August 2014 after winning the World Cup. <P3-S1>  Mertesacker is a youth product of Hannover 96 and he made his senior league debut in November 2003. <P3-S2> Per Mertesacker (] ; born 29 September 1984) is a German professional footballer who plays as a centre back for Premier League club Arsenal. <P3-S3>  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. <P3-S4>  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. <P3-S5>  He has been described as an imposing, reliable, dominant and an accomplished defender.