Question: Who is Fujiwara No Muchimaro's paternal grandfather?

Knowledge 1: Fujiwara no Muchimaro
The eldest son of Fujiwara no Fuhito, he founded the Nanke ("Southern") branch of the Fujiwara clan.Muchimaro's mother was Sogano Shōshi, daughter of Sogano Murajiko.He married a granddaughter of Abeno Miushi, with whom he had two sonsFujiwara no Toyonari and Fujiwara no Nakamaro.Among his daughters was consort of Emperor Shōmu.Muchimaro became the head of Ministry of Civil Services in 718.When Fuhito, Muchimaro's father, died in 720, Prince Nagaya was at the highest rank in the state government.Prince Nagaya was grandson of Emperor Tenmu, but not a son of Fujiwara family, therefore was seen as a threat by Muchimaro and his three brothers.After successfully removing Prince Nagaya in 729, Muchimaro rose to Counselor.In 734, he was promoted to "Udaijin" or "Minister of the Right".In 737, he was made "Sadaijin" or "Minister of the Left", but died of smallpox the following day. [SEP] Knowledge 2: Fujiwara no Fuhito
Fujiwara no Fuhito (藤原 不比等: 659 – September 13, 720) was a powerful member of the imperial court of Japan during the Asuka and Nara periods.Second son of Fujiwara no Kamatari (or, according to one theory, of Emperor Tenji), he had sons by two women, and those sons were the founders of the four principal lineages of the Fujiwara clan: the South, North, Ceremonial, and Capital lineages.Also, he had four daughters by two other women, three by Kamohime, one by Tachibana no Michiyo.One daughter by Kamohime became Emperor Monmu's wife Miyako, who in turn gave birth to Emperor Shōmu.The daughter by Michiyo became the empress of his grandson Shōmu, Empress Kōmyō.During the reign of Emperor Monmu, the government ordered that only the descendants of Fuhito could bear the Fujiwara surname and could be appointed in the Office of Dajokan, the center of administratives.
Knowledge 1: Fujiwara no Muchimaro
The eldest son of Fujiwara no Fuhito, he founded the Nanke ("Southern") branch of the Fujiwara clan.Muchimaro's mother was Sogano Shōshi, daughter of Sogano Murajiko.He married a granddaughter of Abeno Miushi, with whom he had two sonsFujiwara no Toyonari and Fujiwara no Nakamaro.Among his daughters was consort of Emperor Shōmu.Muchimaro became the head of Ministry of Civil Services in 718.When Fuhito, Muchimaro's father, died in 720, Prince Nagaya was at the highest rank in the state government.Prince Nagaya was grandson of Emperor Tenmu, but not a son of Fujiwara family, therefore was seen as a threat by Muchimaro and his three brothers.After successfully removing Prince Nagaya in 729, Muchimaro rose to Counselor.In 734, he was promoted to "Udaijin" or "Minister of the Right".In 737, he was made "Sadaijin" or "Minister of the Left", but died of smallpox the following day. [SEP] Knowledge 2: 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 Yōzei.
Knowledge 1: Fujiwara no Muchimaro
The eldest son of Fujiwara no Fuhito, he founded the Nanke ("Southern") branch of the Fujiwara clan.Muchimaro's mother was Sogano Shōshi, daughter of Sogano Murajiko.He married a granddaughter of Abeno Miushi, with whom he had two sonsFujiwara no Toyonari and Fujiwara no Nakamaro.Among his daughters was consort of Emperor Shōmu.Muchimaro became the head of Ministry of Civil Services in 718.When Fuhito, Muchimaro's father, died in 720, Prince Nagaya was at the highest rank in the state government.Prince Nagaya was grandson of Emperor Tenmu, but not a son of Fujiwara family, therefore was seen as a threat by Muchimaro and his three brothers.After successfully removing Prince Nagaya in 729, Muchimaro rose to Counselor.In 734, he was promoted to "Udaijin" or "Minister of the Right".In 737, he was made "Sadaijin" or "Minister of the Left", but died of smallpox the following day. [SEP] Knowledge 2: Fujiwara no Hiroko
, also known as, was an empress consort of Emperor Go- Reizei.She was the eldest daughter of Fujiwara no Yorimichi and Fujiwara no Gishi.Fujiwara no Morozane was her brother by the same mother.

Answer: Fujiwara no Kamatari