Question: Who is the paternal grandfather of Baha Al-Dawla?

Knowledge 1: Baha al-Dawla
Abu Nasr Firuz Kharshadh (died December 22, 1012), better known by his "laqab" of Baha al-Dawla  was the Buyid amir of Iraq (988–1012), along with Fars and Kerman (998–1012).His early reign was dominated by struggles with his rival relatives over control of the western Persian provinces, but by 998 he managed to establish his supremacy over the Buyid confederation.His reign nevertheless saw the increasing encroachment of neighbouring powers on Buyid territory, and marks the beginning of the decline of the Buyids' power.He was the third son of 'Adud al-Dawla. [SEP] Knowledge 2: 'Adud al-Dawla
Fannā (Panāh) Khusraw , better known by his laqab of ʿAḍud al-Dawla ("Pillar of the [Abbasid] Dynasty")(September 24, 936 – March 26, 983) was an emir of the Buyid dynasty, ruling from 949 to 983, and at his height of power ruling an empire stretching from Makran as far to Yemen and the shores of the Mediterranean Sea.He is widely regarded as the greatest monarch of the dynasty, and by the end of his reign was the most powerful ruler in the Middle East.The son of Rukn al-Dawla, Fanna Khusraw was given the title of Adud al-Dawla by the Abbasid caliph in 948 when he was made emir of Fars after the death of his childless uncleImad al-Dawla, after which Rukn al-Dawla became the senior emir of the Buyids.In 974 Adud al-Dawla was sent by his father to save his cousin Izz al-Dawla from a rebellion.After defeating the rebel forces, he claimed the emirate of Iraq for himself, and forced his cousin to abdicate.His father, however, became angered by this decision and restored Izz al-Dawla.After the death of Adud al-Dawla's father, his cousin rebelled against him, but was defeated.Adud al-Dawla became afterwards the sole ruler of the Buyid dynasty and assumed the ancient Iranian title of Shahanshah ("King of Kings").When Adud al-Dawla became emir of Iraq, the capital city, Baghdad, was suffering from violence and instability owing to sectarian conflict.In order to bring peace and stability to the city, he ordered the banning of public demonstrations and polemics.At the same time, he patronized a number of Shia scholars such as al-Mufid, and sponsored the renovation of a number of important Shia shrines.In addition, 'Adud al-Dawla is credited with sponsoring and patronizing other scientific projects during his time.An observatory was built by his orders in Isfahan where Azophi worked.Al-Muqaddasi also reports that he ordered the construction of a great dam between Shiraz and Estakhr in 960.The dam irrigated some 300 villages in Fars province and became known as "Band-e Amir" (Dam of the emir).Among his other major constructions was the digging of the Haffar channel, that joined the Karun river to the Shatt al-Arab river (the confluence of the Tigris and the Euphrates).The port of Khorramshahr was built on the Haffar, at its joining point with the Shatt al-Arab.
Knowledge 1: Baha al-Dawla
Abu Nasr Firuz Kharshadh (died December 22, 1012), better known by his "laqab" of Baha al-Dawla  was the Buyid amir of Iraq (988–1012), along with Fars and Kerman (998–1012).His early reign was dominated by struggles with his rival relatives over control of the western Persian provinces, but by 998 he managed to establish his supremacy over the Buyid confederation.His reign nevertheless saw the increasing encroachment of neighbouring powers on Buyid territory, and marks the beginning of the decline of the Buyids' power.He was the third son of 'Adud al-Dawla. [SEP] Knowledge 2: Sultan al-Dawla
Abu Shuja( 993 – December 1024), better known by his" laqab" of Sultan al- Dawla( Persian: سلطان الدوله," Power of the Dynasty"), was the Buyid amir of Fars( 1012–1024) and Iraq( 1012 – 1021).He was the son of Baha' al- Dawla.
Knowledge 1: Ali ibn Kama
Ali ibn Kama, the uncle of the Buyid ruler Rukn al- Dawla and the latter's other brothers Mu'izz al- Dawla and Imad al- Dawla, was a Buyid military officer who became prominent among the Buyids of Jibal, and was greatly honored among his Daylamite kinsmen.At the death of Imad al- Dawla in 949, Ali was appointed as the viceroy of Ray by Rukn al- Dawla, who went to Shiraz to secure the succession of his son there, Adud al- Dawla.Meanwhile, the Samanids used this opportunity to invade the territories of Rukn al- Dawla, forcing Ali to flee from Jibal.In ca. 959, a battle ensured between Ali and the Ziyarid prince Bisutun, which resulted in a Buyid victory.In 966, Ali and Rukn al- Dawla defeated a large force of" ghazis" who had arrived from Khorasan.Rukn al- Dawla later died in 976 and was succeeded by his son Fakhr al- Dawla, who had Ali executed. [SEP] Knowledge 2: Ziyar ibn Shahrakuya
Ziyar ibn Shahrakuya( also spelled Shahrakawayh), was a high- ranking Gilaki military officer who served the Buyids.Ziyar was the son of Shahrakawayh, the son of Harusindan, the maternal uncle of the Ziyarid ruler Mardavij.Ziyar had a cousin, who married the Buyid ruler Adud al- Dawla, and bore him one son named Abu Kalijar Marzuban.During that period, Ziyar, along with a Daylamite officer named Fuladh ibn Manadhar, dominated the Buyid court of Baghdad.After the death of Adud al- Dawla in 983, the Buyid Empire was thrown into civil war; the Empire was disputed between his two sons Abu Kalijar Marzuban( who took the name Samsam al- Dawla) and Sharaf al- Dawla.The Turkic soldiers of Iraq shortly betrayed Samsam al- Dawla, and went towards to the court of Sharaf al- Dawla.However, Ziyar managed to make most of them change their mind and stay loyal to Samsam al- Dawla.In 987, Sharaf al- Dawla marched towards Baghdad and deposed Samsam al- Dawla.He then imprisoned Fuladh and had Ziyar executed.

Answer: Rukn al-Dawla