Question: Who is Lulach's maternal grandfather?

Knowledge 1: Lulach
Lulach mac Gille Coemgáin(Modern Gaelic: "Lughlagh mac Gille Chomghain", known in English simply as Lulach, and nicknamed Tairbith, "the Unfortunate" and Fatuus, "the Simple-minded" or "the Foolish"; before 1033 – 17 March 1058) was King of Scots between 15 August 1057 and 17 March 1058.Lulach was the son of Gruoch of Scotland, from her first marriage to Gille Coemgáin, Mormaer of Moray, and thus the stepson of Macbeth (Mac Bethad mac Findlaích).Following the death of Macbeth at the Battle of Lumphanan on 15 August 1057, the king's followers placed Lulach on the throne.He has the distinction of being the first king of Scotland of whom there are coronation details available: he was crowned, probably on 8 September 1057 at Scone.Lulach appears to have been a weak king, as his nicknames suggest, and ruled only for a few months before being assassinated and usurped by Malcolm III.Lulach's son Máel Snechtai was Mormaer of Moray, while Óengus of Moray was the son of Lulach's daughter.He is believed to be buried on Saint Columba's Holy Island of Iona in or around the monastery.The exact position of his grave is unknown. [SEP] Knowledge 2: Gruoch of Scotland
Gruoch ingen Boite  was a Scottish queen, the daughter of Boite mac Cináeda, son of Cináed III.She is most famous for being the wife and queen of MacBethad mac Findlaích (Macbeth).The dates of her life are uncertain.
Knowledge 1: Lulach
Lulach mac Gille Coemgáin(Modern Gaelic: "Lughlagh mac Gille Chomghain", known in English simply as Lulach, and nicknamed Tairbith, "the Unfortunate" and Fatuus, "the Simple-minded" or "the Foolish"; before 1033 – 17 March 1058) was King of Scots between 15 August 1057 and 17 March 1058.Lulach was the son of Gruoch of Scotland, from her first marriage to Gille Coemgáin, Mormaer of Moray, and thus the stepson of Macbeth (Mac Bethad mac Findlaích).Following the death of Macbeth at the Battle of Lumphanan on 15 August 1057, the king's followers placed Lulach on the throne.He has the distinction of being the first king of Scotland of whom there are coronation details available: he was crowned, probably on 8 September 1057 at Scone.Lulach appears to have been a weak king, as his nicknames suggest, and ruled only for a few months before being assassinated and usurped by Malcolm III.Lulach's son Máel Snechtai was Mormaer of Moray, while Óengus of Moray was the son of Lulach's daughter.He is believed to be buried on Saint Columba's Holy Island of Iona in or around the monastery.The exact position of his grave is unknown. [SEP] Knowledge 2: Kaya Alp
Kaya Alp was, according to Ottoman tradition, the son of Kızıl Buğa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertuğrul, and the great grandfather of the Ottoman Empire founder, Osman I.
Knowledge 1: Henry Krause
Henry J." Red" Krause, Jr.( August 28, 1913 – February 20, 1987) was an American football offensive lineman in the National Football League for the Brooklyn Dodgers and the Washington Redskins.He played college football at St. Louis University.He is the grandfather of Jennifer KrauseHe is the great grandfather of Payton Hoeing [SEP] Knowledge 2: Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.He was the grandfather of singer/ poet Leonard Cohen.

Answer: Boite mac Cináeda