Question: Who is the president of the country that issued Stephen Worgu a passport?

full_context: Document 1: President of Nigeria: The President of the Federal Republic of Nigeria is the head of state and head of the national executive of Nigeria. The President of Nigeria is also the commander - in - chief of the Nigerian Armed Forces. The President is elected in national elections which take place every four years. The first President of Nigeria was Nnamdi Azikiwe, who took office on 1 October 1963. The current President, Muhammadu Buhari, took office on 29 May 2015 as the 15th President of the Federal Republic of Nigeria.
Document 2: Niyi Ogunlana: Babatunde Niyi Ogunlana (born August 14, 1984 in Patako) is a former Nigerian football player, who was last playing for Kwara United F.C. of Ilorin.
Document 3: Nigeria: Nigeria is a Federal Republic modelled after the United States, with executive power exercised by the president. It is influenced by the Westminster System model[citation needed] in the composition and management of the upper and lower houses of the bicameral legislature. The president presides as both Head of State and head of the national executive; the leader is elected by popular vote to a maximum of two 4-year terms. In the March 28, 2015 presidential election, General Muhammadu Buhari emerged victorious to become the Federal President of Nigeria, defeating then incumbent Goodluck Jonathan.
Document 4: Deputy President of the Nigerian Senate: Deputy Senate Presidents of Nigeria Deputy Senate President Term Party Ibrahim Mantu 1999 - 2007 PDP Ike Ekweremadu 2007 - present PDP
Document 5: Nigeria: Football is largely considered the Nigeria's national sport and the country has its own Premier League of football. Nigeria's national football team, known as the "Super Eagles", has made the World Cup on five occasions 1994, 1998, 2002, 2010, and most recently in 2014. In April 1994, the Super Eagles ranked 5th in the FIFA World Rankings, the highest ranking achieved by an African football team. They won the African Cup of Nations in 1980, 1994, and 2013, and have also hosted the U-17 & U-20 World Cup. They won the gold medal for football in the 1996 Summer Olympics (in which they beat Argentina) becoming the first African football team to win gold in Olympic Football.
Document 6: Nigeria national football team: Nigeria Nickname (s) Super Eagles Association Nigeria Football Federation Confederation CAF (Africa) Sub-confederation WAFU (West Africa) Head coach Gernot Rohr Captain John Mikel Obi Top scorer Rashidi Yekini (37) Home stadium Abuja National Stadium FIFA code NGA First colours Second colours FIFA ranking Current 49 1 (16 August 2018) Highest 5 (April 1994) Lowest 82 (November 1999) Elo ranking Current 44 (11 July 2018) Highest 15 (31 May 2004) Lowest 72 (27 December 1964) First international Sierra Leone 0 -- 2 Nigeria (Freetown, Sierra Leone; 8 October 1949) Biggest win Nigeria 10 -- 1 Dahomey (Lagos, Nigeria; 28 November 1959) Biggest defeat Gold Coast and British Togoland 7 -- 0 Nigeria (Accra, Gold Coast; 1 June 1955) World Cup Appearances 6 (first in 1994) Best result Round of 16 (1994, 1998, 2014) Africa Cup of Nations Appearances 17 (first in 1963) Best result Champions (1980, 1994, 2013) African Nations Championship Appearances 3 (first in 2014) Best result Runners up (2018) Confederations Cup Appearances 2 (first in 1995) Best result Fourth Place (1995) Medal record (show) Men's football Olympic Games 1996 Atlanta Team
Document 7: Alex Waimora: Alex Allen Waimora is a Solomon Islands international football player. Formerly a member of Three Kings in the New Zealand ASB Youth League. He has played for Solomon Islands U14&U15 Futsal Team in 2009 and 2010. He later played in 2011 edition of the Oceania FIFA U17 World Cup Qualifiers for Solomon Islands. He has made 1 appearance for the Solomon Islands national football team.
Document 8: Stephen López: Stephen López (born September 24, 1980) is a Belizean professional footballer who plays as a goalkeeper for Suga Boys Juventus.
Document 9: United States Senate: The presiding officer of the Senate is the Vice President of the United States, who is President of the Senate. In the Vice President's absence, the President Pro Tempore, who is customarily the senior member of the party holding a majority of seats, presides over the Senate. In the early 20th century, the practice of majority and minority parties electing their floor leaders began, although they are not constitutional officers.
Document 10: Vice President of Nigeria: The Vice President of Nigeria is the second - in - command to the President of Nigeria in the Government of Nigeria. Officially styled Vice President of the Federal Republic of Nigeria, the Vice President is elected alongside the President in national elections. The office is currently held by Yemi Osinbajo.
Document 11: Age of candidacy: In Nigeria, a person must be at least 35 years of age to be elected President or Vice President, 30 to be a Senator or State Governor, and 25 to be a Representative in parliament.
Document 12: Nigeria national football team: Nigeria Nickname (s) Super Eagles Association Nigeria Football Federation Confederation CAF (Africa) Sub-confederation WAFU (West Africa) Head coach Gernot Rohr Captain John Obi Mikel Most caps Vincent Enyeama (101) Joseph Yobo (101) Top scorer Rashidi Yekini (37) Home stadium Abuja National Stadium FIFA code NGA First colours Second colours FIFA ranking Current 47 5 (12 April 2018) Highest 5 (April 1994) Lowest 82 (November 1999) Elo ranking Current 43 (8 April 2018) Highest 15 (31 May 2004) Lowest 72 (27 December 1964) First international Sierra Leone 0 -- 2 Nigeria (Freetown, Sierra Leone; 8 October 1949) Biggest win Nigeria 10 -- 1 Dahomey (Lagos, Nigeria; 28 November 1959) Biggest defeat Gold Coast and British Togoland 7 -- 0 Nigeria (Accra, Gold Coast; 1 June 1955) World Cup Appearances 6 (first in 1994) Best result Round of 16, 1994, 1998 and 2014 Africa Cup of Nations Appearances 17 (first in 1963) Best result Champions, 1980, 1994 and 2013 African Nations Championship Appearances 3 (first in 2014) Best result Runners up, 2018 Confederations Cup Appearances 2 (first in 1995) Best result Fourth Place, 1995
Document 13: Georgia State Senate: The presiding officer of the Senate is the President of the Senate. A President Pro Tempore, usually a high - ranking member of the majority party, acts as President in case of the temporary disability of the President. In case of the death, resignation, or permanent disability of the President or in the event of the succession of the President to the executive power, the President Pro Tempore becomes President. The Senate also has as an officer the Secretary of the Senate.
Document 14: Stephen Worgu: Stephen Worgu (born 6 April 1990 in Brass, Nigeria) is a Nigerian footballer who plays for Bowsher Club in Oman.
Document 15: President of the Senate of Nigeria: The President of the Senate is the presiding officer of the Senate of Nigeria, elected by its membership. The Senate President is second in line for succession to the Nigerian presidency, after the Vice President of Nigeria. The current President of the Senate is Bukola Saraki.
ground_truth: Bukola Saraki
sub_queries: What is Stephen Worgu's country of citizenship? Answer: Nigeria
who is the president of the senate in Nigeria Answer: Bukola Saraki