Question: Who was Archduchess Maria Anna of Austria's grandfather on her mothers side?
Context: Marie Anne Franziska Theresia Josepha Medarde of Austria (8 June 1804 – 28 December 1858) was an Archduchess of Austria and the daughter of Franz II, Holy Roman Emperor and his second wife, Maria Theresa of Naples and Sicily. Archduchess Maria Anna of Austria (German: "Maria Anna von Habsburg, Erzherzogin von Österreich", also known as "Maria Anna von Bayern" or "Maria-Anna, Kurfürstin von Bayern"; 13 January 1610 – 25 September 1665), was by birth Archduchess of Austria and member of the House of Habsburg and by marriage Electress of Bavaria. Archduchess Maria Anna of Austria (27 October 1835 – 5 February 1840), was by birth an Archduchess of Austria and member of the House of Habsburg. Archduchess Maria Carolina of Austria (full German name: "Maria Carolina Ernestina Antonia Johanna Josefa"; 12 January 1740 – 25 January 1741), was the third child and daughter of Archduchess Maria Theresa of Austria, later Holy Roman Empress and Duke Francis of Lorraine. Archduchess Maria Anna of Austria ("Maria Anna Ferdinanda Josepha Charlotte Johanna"; 21 April 1770 - 1 October 1809) was an Archduchess of Austria by birth, and an Abbess at the Theresian Convent in Prague. Archduchess Maria Antonia of Austria German: "Maria Antonia, Erzherzogin von Österreich-Toskana" (13 July 1899 – 22 October 1977) was a daughter of Archduke Leopold Salvator of Austria and Infanta Blanca of Spain.  She was member of the Tuscan branch of the Imperial House of Habsburg, an Archduchess of Austria and Princess of Tuscany by birth.  In 1919, after the fall of the Austro Hungary Empire, she moved with her family to Spain.  In 1924 she married Ramón de Orlandis y Villalonga, a Spanish aristocrat.  When she became a widow during the Spanish civil war Archduchess Maria Antonia moved permanently to South America where she remarried. Archduchess Maria Anna Eleanor Wilhelmina Josepha of Austria (18 September 1718 in Vienna – 16 December 1744 in Brussels) was an Archduchess of Austria and a Princess of Lorraine, the younger sister of Empress Maria Theresa, and a Governor of the Austrian Netherlands. Maria Theresa of Naples and Sicily (6 June 1772 – 13 April 1807) was the last Holy Roman Empress and the first Empress of Austria by marriage to Francis II, Holy Roman Emperor.  She was the eldest daughter of Ferdinand IV & III of Naples and Sicily (later Ferdinand I of the Two Sicilies) (1751–1825) and his wife, Marie Caroline of Austria (1752–1814). Giuseppe Tominz was born in Gorizia as the second of eleven children of Ivano Tominz, an Italian dealer in ironware of distant Slovene origin, and his wife Maria Anna Giacchini, a native Italian woman of Udine.  He was educated in an Italian-speaking environment.  He attended a primary school run by Piarists in Gorizia, where he began to learn to paint in the third year.  He received his first training as a painter from the local artist Karel Keber and probably also from the painter Franz Caucig.  In 1809, he left for Rome with the help of Austrian Archduchess Maria Anna, sister of Emperor Francis I of Austria, and count Francesco della Torre.  In Rome, he studied painting with Domenico Conti Bazzani and in the Scuola del Nudo at the Accademia di San Luca.  In 1814, he was awarded a silver medal for his drawing "Study of the Apostople".  Two years later, he married Maria Ricci and in 1818, have two son Augusto and Alfredo will become the first director of the Revoltella Museum in Trieste.  In the same year, Tominz returned with his family to Gorizia.  Of his early artistic works, several anatomical studies, sketches and one of his landscapes "View of Vietri, Rieti and the Salerno Bay" have survived. Archduchess "Maria Anna" Isabelle Epiphanie Eugenie Gabriele of Austria, full German name: "Maria Anna Isabelle Epiphanie Eugenie Gabriele, Erzherzogin von Österreich" (6 January 1882, Linz, Upper Austria, Austria–Hungary – 25 February 1940, Lausanne, Vaud, Switzerland) was a member of the Teschen branch of the House of Habsburg-Lorraine and an Archduchess of Austria and Princess of Bohemia, Hungary, and Tuscany by birth.  Through her marriage to Prince Elias of Bourbon-Parma (later Duke of Parma), Maria Anna was also a member of the House of Bourbon-Parma and a Princess of Bourbon-Parma.
Answer: Ferdinand IV