Question: What is the cause of death of Turki Bin Abdullah Al Saud's father?

Knowledge 1: 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. [SEP] Knowledge 2: Abdullah of Saudi Arabia
Abdullah bin Abdulaziz Al Saud(Najdi Arabic pronunciation: ; 1 August 1924 – 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'état.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.
Knowledge 1: 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. [SEP] Knowledge 2: 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.
Knowledge 1: 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. [SEP] Knowledge 2: 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.

Answer: pneumonia