question: What is the cause of death of Turki Bin Abdullah Al Saud's father?
context: [["Abdul Rahman bin Faisal", ["Abdul Rahman bin Faisal Al Saud( 1845\u20131928)(/ ALA- LC:\" \u2018 Abd ar Ra\u1e25man bin Fay\u1e63al\") was the last ruler of the Emirate of Nejd, Second Saudi State.", "He was the youngest son of Faisal bin Turki bin Abdullah Al Saud and the father of Ibn Saud, who founded the modern Saudi Arabia."]], ["Turki bin Talal bin Abdul Aziz Al Saud", ["Turki bin Talal bin AbdulAziz Al Saud is a member of the House of Saud.", "He is the Governor of Asir."]], ["Turki bin Nasser Al Saud", ["Turki bin Nasser Al Saud( born 14 April 1948) is the former head of the presidency of meteorology and environment in Saudi Arabia and a member of House of Saud."]], ["Fahd bin Abdullah bin Mohammed Al Saud", ["Fahd bin Abdullah Al Saud is the former deputy defence minister of Saudi Arabia and a member of the House of Saud."]], ["Sultan bin Abdullah bin Aziz Al Saud", ["Sultan bin Abdullah bin Aziz Al Saud is a son of the late Saudi King, Abdullah bin Abdul Aziz Al Saud, who was the sixth king of the Saudi Kingdom."]], ["Abdullah bin Mutaib Al Saud", ["Abdullah bin Mutaib bin Abdullah Al Saud( born 13 October 1984) is a Saudi show jumping rider and a member of House of Saud."]], ["Khalid bin Abdullah Al Khalifa", ["Khalid bin Abdullah Al Khalifa is a Bahraini royal and deputy prime minister of Bahrain."]], ["Faisal bin Turki I bin Abdulaziz Al Saud", ["Faisal bin Turki", "I bin Abdulaziz Al Saud( 1918 \u2013 1968), was the only son of Turki I bin Abdulaziz Al Saud and the eldest grandson of Abdulaziz Ibn Saud.", "He served as minister of interior during the reign of King Saud and was first minister of labour and social affairs."]], ["Turki bin Abdullah Al Saud", ["Turki bin Abdullah Al Saud  (", "born 21 October 1971) is the seventh son of the late King Abdullah bin Abdulaziz, who ruled Saudi Arabia from 2005 until his death in 2015 and a member of the House of Saud.", "He served as deputy governor of Riyadh Province from 2013 to 2014 and as governor of Riyadh Province from 14 May 2014 to 29 January 2015.", "He was one of the 11 princes detained by Mohammad bin Salman as a part of his anti-corruption drive, on accusations of corruption in the Riyadh Metro project and taking advantage of his influence to award contracts to his own companies."]], ["Abdullah of Saudi Arabia", ["Abdullah bin Abdulaziz Al Saud", "(Najdi Arabic pronunciation: ; 1 August 1924 \u2013 23 January 2015) was King of Saudi Arabia and Custodian of the Two Holy Mosques from 2005 to his death in 2015.", "He ascended to the throne on 1 August 2005 upon the death of his half-brother, King Fahd.", "Abdullah, like Fahd, was one of the many sons of Ibn Saud, the founder of modern Saudi Arabia.", "Abdullah held important political posts throughout most of his adult life.", "In 1961 he became mayor of Mecca, his first public office.", "The following year, he was appointed commander of the Saudi Arabian National Guard, a post he was still holding when he became king.", "He also served as deputy defense minister and was named crown prince when Fahd took the throne in 1982.", "After King Fahd suffered a serious stroke in 1995, Abdullah became the \"de facto\" ruler of Saudi Arabia until ascending the throne a decade later.", "During his reign he maintained close relations with United States and United Kingdom and bought billions of dollars worth of defense equipment from both states.", "He also gave women the right to vote for municipal councils and to compete in the Olympics.", "Furthermore, Abdullah maintained the status quo when there were waves of protest in the kingdom during the Arab Spring.", "In November 2013, a BBC report claimed that, due to the close relations it had with Pakistan, Saudi Arabia could obtain nuclear weapons at will from that country.", "The King also had a longstanding relationship with Pakistan, and brokered a compromise between ousted Prime Minister Nawaz Sharif and General Pervez Musharraf, whom he had requested to be exiled to Saudi Arabia for a 10-year exile, following his ouster in the 1999 Pakistani coup d'\u00e9tat.", "The King outlived two of his crown princes.", "Conservative Interior Minister Nayef bin Abdul-Aziz Al Saud was named heir to the throne on the death of Sultan bin Abdulaziz in October 2011, but Nayef himself died in June 2012.", "Abdullah then named 76-year-old defense minister, Salman bin Abdulaziz Al Saud, as crown prince.", "According to various reports, Abdullah married up to 30 times and had more than 35 children.", "The king had a personal fortune estimated at US$18 billion, making him the third wealthiest head of state in the world.", "He died on 23 January 2015, at the age of 90, three weeks after being hospitalized for pneumonia, and was succeeded as king by his half-brother Salman of Saudi Arabia."]]]
supporting_facts: [["Turki bin Abdullah Al Saud", 1], ["Abdullah of Saudi Arabia", 19]]
evidences: [["Turki bin Abdullah Al Saud", "father", "King Abdullah"], ["Abdullah of Saudi Arabia", "cause of death", "pneumonia"]]
answer: pneumonia