question: Who is the paternal grandfather of Euphemia Of Pomerania?
context: [["Euphemia of Pomerania", ["Euphemia of Pomerania (1285 \u2013 26 July 1330) was Queen of Denmark as the spouse of King Christopher II.", "She was the daughter of Bogislaw IV, Duke of Pomerania, and his second spouse, Margarete of R\u00fcgen.", "Euphemia wed Christopher in 1300.", "The marriage was likely a politically arranged marriage to provide Christopher with political support from the dynasty of her mother as well as that of her father.", "Not much is known about queen Euphemia.", "Euphemia had at least six known children:", "She is buried in the Sor\u00f8 Abbey."]], ["Abd al-Muttalib", ["Abd al- Muttalib Shaybah ibn Hashim( c. 497 \u2013 578) was the grandfather of Islamic prophet Muhammad."]], ["Kaya Alp", ["Kaya Alp was, according to Ottoman tradition, the son of K\u0131z\u0131l Bu\u011fa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertu\u011frul, and the great grandfather of the Ottoman Empire founder, Osman I."]], ["Prithvipati Shah", ["Prithvipati Shah( ?\u20131716) was the king of the Gorkha Kingdom in the Indian subcontinent, present- day Nepal.", "He was the grandfather of Nara Bhupal Shah."]], ["Bogislaw IV, Duke of Pomerania", ["Bogislaw IV (died 19 February 1309 or 24 February 1309), of the Griffins dynasty, was Duke of Pomerania for thirty years.", "Bogislaw was the eldest son of Duke Barnim I by his second wife, sometimes said to be a daughter of King Eric X of Sweden.", "He was an adult at his father's death in 1278, having been co-ruler since 1276.", "His half-brothers Barnim II and Otto I were still very young and so he was sole ruler in Pomerania during their minority.", "In the early 1280s Bogislaw was involved in the war in the neighbouring margraviate of Brandenburg.", "At this time he married Matilda, daughter of John I and a sister of reigning Margrave Otto IV, but all of his known children were by a second marriage to Margarete, daughter of Wizlaw II, Prince of R\u00fcgen.", "In the 1290s with his brothers now adults, Pomerania was divided between them with Bogislaw receiving Wolgast as his share.", "Barnim II died soon afterwards and Otto ruled Szczecin.", "In the 14th century, he was allied with would-be King of Poland W\u0142adys\u0142aw the Short.", "He was unsuccessfully involved in the opening stages of the decade-long .", "He died in 1309 leaving his share of Pomerania to his son Wartislaw."]], ["Guillaume Wittouck", ["Guillaume Wittouck( 1749- 1829) was a Belgian lawyer and High Magistrate.", "He was the Grandfather of industrialist Paul Wittouck."]], ["Lyon Cohen", ["Lyon Cohen( 1868\u20131937) was a Polish- born Canadian businessman and a philanthropist.", "He was the grandfather of singer/ poet Leonard Cohen."]], ["Fujiwara no Nagara", [", also known as Fujiwara no Nagayoshi, was a Japanese statesman, courtier and politician of the early Heian period.", "He was the grandfather of Emperor Y\u014dzei."]], ["John Westley", ["Rev. John Westley( 1636 \u2013 78) was an English nonconformist minister.", "He was the grandfather of John Wesley( founder of Methodism)."]], ["Margaret of Masovia", ["Margaret of Masovia( before 1358 \u2013 14 May 1388/4 April 1396) was Duchess of Pomerania and Brzeg, by her marriages to Casimir IV, Duke of Pomerania and then to Henryk VIII with a Scar.", "She was a member of the House of Piast.", "Margaret was a daughter of Siemowit III of Masovia and his wife Euphemia of Opawa.", "Her paternal grandparents were Trojden I of Masovia and his wife Maria, daughter of Yuri I of Galicia and Euphemia of Kuyavia."]]]
supporting_facts: [["Euphemia of Pomerania", 1], ["Bogislaw IV, Duke of Pomerania", 1]]
evidences: [["Euphemia of Pomerania", "father", "Bogislaw IV, Duke of Pomerania"], ["Bogislaw IV, Duke of Pomerania", "father", "Barnim I"]]
answer: Barnim I