Question: Who is Ferdinand I Of The Two Sicilies's paternal grandfather?

Knowledge 1: Ferdinand I of the Two Sicilies
Ferdinand I (12 January 1751 – 4 January 1825), was the King of the Two Sicilies from 1816, after his restoration following victory in the Napoleonic Wars.Before that he had been, since 1759, Ferdinand IV of the Kingdom of Naples and Ferdinand III of the Kingdom of Sicily.He was also King of Gozo.He was deposed twice from the throne of Naples: once by the revolutionary Parthenopean Republic for six months in 1799 and again by Napoleon Bonaparte in 1805.Ferdinand was the third son of King Charles VII of Naples and V of Sicily by his wife, Maria Amalia of Saxony.On 10 August 1759, Charles succeeded his elder brother, Ferdinand VI, becoming King Charles III of Spain, but treaty provisions made him ineligible to hold all three crowns.On 6 October, he abdicated his Neapolitan and Sicilian titles in favour of his third son, because his eldest son Philip had been excluded from succession due to illnesses and his second son Charles was heir to the Spanish throne.Ferdinand was the founder of the cadet House of Bourbon-Two Sicilies. [SEP] Knowledge 2: Charles III of Spain
Charles III (Spanish: "Carlos"; Italian: "Carlo"; 20 January 1716 – 14 December 1788) was King of Spain (1759–1788), after ruling Naples as Charles VII and Sicily as Charles V (1734–1759).He was the fifth son of Philip V of Spain, and the eldest son of Philip's second wife, Elisabeth Farnese.A proponent of enlightened absolutism, he succeeded to the Spanish throne on 10 August 1759, upon the death of his half-brother Ferdinand VI, who left no heirs.In 1731, the 15-year-old Charles became the Duke of Parma and Piacenza, as Charles I, following the death of his childless grand-uncle Antonio Farnese.In 1738 he married Princess Maria Amalia of Saxony, daughter of Augustus III of Poland and an educated, cultured woman who gave birth to 13 children, eight of whom reached adulthood.Charles and Maria Amalia resided in Naples for 19 years.As King of Spain, Charles III made far-reaching reforms such as promoting science and university research, facilitating trade and commerce, and modernising agriculture.He also tried to reduce the influence of the Church and strengthen the Spanish army and navy.His previous experience as King of Naples and Sicily proved valuable.He did not achieve complete control over Spain's finances, and was sometimes obliged to borrow to meet expenses, but most of his reforms proved to be successful and his legacy lives on to this day.Historian Stanley Payne wrote that Charles III "was probably the most successful European ruler of his generation.He had provided firm, consistent, intelligent leadership.He had chosen capable ministers...[his] personal life had won the respect of the people."
Knowledge 1: Charles III of Spain
Charles III (Spanish: "Carlos"; Italian: "Carlo"; 20 January 1716 – 14 December 1788) was King of Spain (1759–1788), after ruling Naples as Charles VII and Sicily as Charles V (1734–1759).He was the fifth son of Philip V of Spain, and the eldest son of Philip's second wife, Elisabeth Farnese.A proponent of enlightened absolutism, he succeeded to the Spanish throne on 10 August 1759, upon the death of his half-brother Ferdinand VI, who left no heirs.In 1731, the 15-year-old Charles became the Duke of Parma and Piacenza, as Charles I, following the death of his childless grand-uncle Antonio Farnese.In 1738 he married Princess Maria Amalia of Saxony, daughter of Augustus III of Poland and an educated, cultured woman who gave birth to 13 children, eight of whom reached adulthood.Charles and Maria Amalia resided in Naples for 19 years.As King of Spain, Charles III made far-reaching reforms such as promoting science and university research, facilitating trade and commerce, and modernising agriculture.He also tried to reduce the influence of the Church and strengthen the Spanish army and navy.His previous experience as King of Naples and Sicily proved valuable.He did not achieve complete control over Spain's finances, and was sometimes obliged to borrow to meet expenses, but most of his reforms proved to be successful and his legacy lives on to this day.Historian Stanley Payne wrote that Charles III "was probably the most successful European ruler of his generation.He had provided firm, consistent, intelligent leadership.He had chosen capable ministers...[his] personal life had won the respect of the people." [SEP] Knowledge 2: Prince Ferdinand, Duke of Castro
Prince Ferdinand of Bourbon-Two Sicilies, The Duke of Castro(Ferdinando Maria Andrea Alfonso Marcus; 28 May 1926 – 20 March 2008) was a claimant to the headship of the former Royal House of the Two Sicilies.
Knowledge 1: Ferdinand I of the Two Sicilies
Ferdinand I (12 January 1751 – 4 January 1825), was the King of the Two Sicilies from 1816, after his restoration following victory in the Napoleonic Wars.Before that he had been, since 1759, Ferdinand IV of the Kingdom of Naples and Ferdinand III of the Kingdom of Sicily.He was also King of Gozo.He was deposed twice from the throne of Naples: once by the revolutionary Parthenopean Republic for six months in 1799 and again by Napoleon Bonaparte in 1805.Ferdinand was the third son of King Charles VII of Naples and V of Sicily by his wife, Maria Amalia of Saxony.On 10 August 1759, Charles succeeded his elder brother, Ferdinand VI, becoming King Charles III of Spain, but treaty provisions made him ineligible to hold all three crowns.On 6 October, he abdicated his Neapolitan and Sicilian titles in favour of his third son, because his eldest son Philip had been excluded from succession due to illnesses and his second son Charles was heir to the Spanish throne.Ferdinand was the founder of the cadet House of Bourbon-Two Sicilies. [SEP] Knowledge 2: Prince Ferdinand, Duke of Castro
Prince Ferdinand of Bourbon-Two Sicilies, The Duke of Castro(Ferdinando Maria Andrea Alfonso Marcus; 28 May 1926 – 20 March 2008) was a claimant to the headship of the former Royal House of the Two Sicilies.

Answer: Philip V