Question: Who is Claire Annabel Caroline Grant Duff's paternal grandfather?

Knowledge 1: Claire Annabel Caroline Grant Duff
Claire Annabel Caroline Grant Duff (25 December 1870 – 12 January 1944) was a poet, writer and high society hostess.She published her memoir "A Victorian Childhood" in 1932 with Methuen Publishing.She was the eldest daughter of Sir Mountstuart Grant Duff and Anna Julia Webster.She was the author of "A Victorian Childhood", which was published in 1932, under the pen name Annabel Jackson.In 1894, she married in Frederick Huth Jackson, a partner in the private bank, Frederick Huth and Sons.They had one son, Frederick who married Helen Vinogradoff, daughter of the distinguished historian Sir Paul Vinogradoff, and three daughters: Konradin, later Lady Arthur Hobhouse; Anne, later Anne Fremantle; and Claire, later Countess de Loriol Chandieu. [SEP] Knowledge 2: M. E. Grant Duff
Sir Mountstuart Elphinstone Grant Duff (21 February 1829 – 12 January 1906), known as M. E. Grant Duff before 1887 and as Sir Mountstuart Grant Duff thereafter, was a Scottish politician, administrator and author.He served as the Under-Secretary of State for India from 1868 to 1874, Under-Secretary of State for the Colonies from 1880 to 1881 and the Governor of Madras from 1881 to 1886.He was born in Eden, Aberdeenshire, on 21 February 1829 to the distinguished British historian James Grant Duff.He had his education at Grange School and Balliol College, Oxford and graduated in law from the Inns of Court.He practised and taught law for a short time before starting a political life and entering the House of Commons as the Liberal Member of Parliament for Elgin Burghs.His abilities won him government positions and he was Under-Secretary of State for India, Under-Secretary of State for the Colonies and Governor of Madras.On his return from Madras, he retired from politics and served in various art and scientific societies.He travelled extensively and wrote voluminously.His performance in politics and administration has received mixed reviews during the 1880s
a politician of brilliant promise and scant performance, of wide information which he seemed to turn to much account, of abilities which would have made the fortunes of half a dozen men and of which he made little enough.He was made a Companion of the Order of the Indian Empire and a Grand Commander of the Order of the Star of India.He died on 12 January 1906 at the age of 76.
Knowledge 1: Claire Annabel Caroline Grant Duff
Claire Annabel Caroline Grant Duff (25 December 1870 – 12 January 1944) was a poet, writer and high society hostess.She published her memoir "A Victorian Childhood" in 1932 with Methuen Publishing.She was the eldest daughter of Sir Mountstuart Grant Duff and Anna Julia Webster.She was the author of "A Victorian Childhood", which was published in 1932, under the pen name Annabel Jackson.In 1894, she married in Frederick Huth Jackson, a partner in the private bank, Frederick Huth and Sons.They had one son, Frederick who married Helen Vinogradoff, daughter of the distinguished historian Sir Paul Vinogradoff, and three daughters: Konradin, later Lady Arthur Hobhouse; Anne, later Anne Fremantle; and Claire, later Countess de Loriol Chandieu. [SEP] Knowledge 2: Arthur Grant Duff
Sir Arthur Cuninghame Grant Duff, (23 May 1861 – 11 April 1948) was a British diplomat who was Minister to several countries.
Knowledge 1: M. E. Grant Duff
Sir Mountstuart Elphinstone Grant Duff (21 February 1829 – 12 January 1906), known as M. E. Grant Duff before 1887 and as Sir Mountstuart Grant Duff thereafter, was a Scottish politician, administrator and author.He served as the Under-Secretary of State for India from 1868 to 1874, Under-Secretary of State for the Colonies from 1880 to 1881 and the Governor of Madras from 1881 to 1886.He was born in Eden, Aberdeenshire, on 21 February 1829 to the distinguished British historian James Grant Duff.He had his education at Grange School and Balliol College, Oxford and graduated in law from the Inns of Court.He practised and taught law for a short time before starting a political life and entering the House of Commons as the Liberal Member of Parliament for Elgin Burghs.His abilities won him government positions and he was Under-Secretary of State for India, Under-Secretary of State for the Colonies and Governor of Madras.On his return from Madras, he retired from politics and served in various art and scientific societies.He travelled extensively and wrote voluminously.His performance in politics and administration has received mixed reviews during the 1880s
a politician of brilliant promise and scant performance, of wide information which he seemed to turn to much account, of abilities which would have made the fortunes of half a dozen men and of which he made little enough.He was made a Companion of the Order of the Indian Empire and a Grand Commander of the Order of the Star of India.He died on 12 January 1906 at the age of 76. [SEP] Knowledge 2: James Grant Duff
James Grant Duff (8 July 1789 – 23 September 1858) was a British soldier and historian from Scotland, who was active in British India.

Answer: James Grant Duff