Question: Ruth Williams Khama, Lady Khama, was the wife of the first President of Botswana, in office from 1966 to 1980, his name? 

Context paragraphs:
Mma-Besi: Mma-Besi or Mabisa (1846-1889) was the mohumagadi (queen or queen mother) of the BaNgwato of the Bechuanaland Protectorate, now Botswana, and the first wife of king Khama III.  She was baptized Elizabeta in 1862, taking the name in honor of Elizabeth Moffat, daughter of Robert Moffat.  She was married that same year in what was the first Christian marriage held in Shoshong.  Her first child, a daughter, was called Besi, and so she became Mma-Besi due to a tradition of taking the name "mother of" one's firstborn.  Her one son who lived, Sekgoma, became king when Khama III died in 1923 but died himself soon after.  She herself died at age 44, likely of malaria due to Khama III moving the capital to the Tswapong Hills, an unhealthy place.

Parliament of Botswana: The Parliament of Botswana consists of the President and the National Assembly.  In contrast to other Parliamentary systems, the Parliament elects the President directly (instead of having both a ceremonial President and a Prime Minister who has real authority as head of government) for a set five-year term of office.  There are no term limits.  The President is both head of State and of Government in Botswana's parliamentary republican system.  The current President of Botswana is Ian Khama, who assumed the Presidency on 1 April 2008 and won a full five-year term in the postceding Botswana General elections, which were held on 16 October 2009 and returned his Botswana Democratic Party with a majority of 35 (total of 45) seats in the 61 seat Parliament.

A United Kingdom: A United Kingdom is a 2016 British biographical romantic drama film directed by Amma Asante and written by Guy Hibbert, based on the true-life romance between Sir Seretse Khama and his wife Ruth Williams Khama.  David Oyelowo and Rosamund Pike portray Seretse and Ruth, respectively.

Ruth Williams Khama: Ruth Williams Khama, Lady Khama (9 December 1923 – 22 May 2002) was the wife of Botswana's first president Sir Seretse Khama, the Paramount Chief of its Bamangwato tribe.  She served as the inaugural First Lady of Botswana from 1966 to 1980.

Seretse Khama: Sir Seretse Goitsebeng Maphiri Khama, GCB, KBE (1 July 1921 – 13 July 1980) was the first President of Botswana, in office from 1966 to 1980.

Sir Seretse Khama International Airport: Sir Seretse Khama International Airport (IATA: GBE, ICAO: FBSK) , located 15 km north of Gaborone, is the main international airport of the capital city of Botswana.  The airport is named after Sir Seretse Khama, the first president of Botswana.  It was opened in 1984 and offers limited capacity to handle regional and (especially)international traffic.  Nonetheless, it has the largest passenger movement in the country.

List of heads of government of Botswana: The office of Prime Minister of Botswana existed from 3 March 1965 to 30 September 1966, during which time it was held by one individual, Seretse Khama, who later served as President from 1966 until his death on 13 July 1980.

First Lady of Botswana: The First Lady of the Republic of Botswana is the title used by the wife of the President of Botswana.  Botswana's inaugural First Lady was Lady Ruth Williams Khama, the English-born wife of the country's inaugural President, Seretse Khama.

Bechuanaland general election, 1965: General elections were held in the Bechuanaland Protectorate on 1 March 1965, the country's first election under universal suffrage.  The result was a landslide victory for the Bechuanaland Democratic Party, with Seretse Khama becoming Prime Minister.  Following the elections, the country became independent as Botswana on 30 September 1966, at which point Khama became President.  Voter turnout was 74.55% of the 188,950 registered voters.

Tshekedi Khama II: Tshekedi Stanford Khama (born 9 June 1958) is a Botswana Member of Parliament from Serowe North-West.  He is a member of the Botswana Democratic Party (BDP).  He is also the brother of the current President of Botswana, Ian Khama, and one of the three sons of the first President of Botswana, Seretse Khama and Ruth Williams Khama.

Supporting paragraphs: Ruth Williams Khama Seretse Khama
Answer: Seretse Goitsebeng Maphiri Khama