Question: The United Democratic Front was formed in opposition to the Pakistani party of which Prime Minister, who served from 1973-77?

Context paragraphs:
Kerala Congress (B): Kerala Congress (B) is a registered-unrecognized political party in Kerala, formed by R. Balakrishna Pillai, a former minister of the government of Kerala.  At present, the party has one MLA in the state Legislative Assembly, namely K. B. Ganesh Kumar, a well-known film actor and son of R. Balakrishna Pillai, who has been representing the Pathanapuram constituency in Kollam District since 2001.  The Kerala Congress (B) was a constituent of the Congress-led United Democratic Front (UDF) until 2016 and is now part of Left Democratic Front.  K B Ganesh Kumar served as a minister (portfolio in Forest, Sports and Cinema) in the UDF government led by Oommen Chandy beginning May 18, 2011 until his resignation on April 1, 2013.

Left Democratic Front (Kerala): Left Democratic Front ("LDF") is a coalition of political parties in the state of Kerala, in India.  It is one of the two major political coalitions in Kerala, the other being the United Democratic Front each of which have been in power alternatively for the last two decades.  LDF won the May 2016 election, and is now in power.  The coalition consists of Communist Party of India (CPI), Communist Party of India (Marxist) (CPI(M)) and variety of other smaller parties.

All India United Democratic Front: The All India United Democratic Front (also known as AIUDF and "Sarva Bharatiya Sanyukt Ganatantric Morcha") is a political party in the India that originated in the north-eastern state of Assam.  It is led by Maulana Badruddin Ajmal, who established the party in October 2005 as a state party, then known as "Assam United Democratic Front" (AUDF).  It was relaunched as a national party under its current name at a press meet in New Delhi on 2nd Feb 2009.  The party's headquarter is in Guwahati.

Swaziland United Democratic Front: The Swaziland United Democratic Front is a coalition of pro-democracy interests including political parties, unions and churches. The Swaziland United Democratic Front was formed on 2 February 2008 at the Tum’s George Hotel in Manzini, Swaziland, attended by 120 persons from various organizations but mainly from the following:

United Democratic Front (Mizoram): United Democratic Front is a front of eight political parties (Mizo National Front, Mizoram People's Conference, Zoram Nationalist Party, Maraland Democratic Front, Hmar People's Convention, Paite Tribes Council, Bharatiya Janata Party, and Nationalist Congress Party) in the Indian state of Mizoram.  The front fielded Robert Romawia Royte for Mizoram's lone Lok Sabha constituency in the 2014 Indian general election.  Founded in March 2014, it supports the National Democratic Alliance (NDA).  It was agreed that, if Royte wins the election, he would support the NDA in the Lok Sabha.  Royte lost the election to Indian National Congress' C. L. Ruala by a margin of 11,361 votes.

United Democratic Front (Pakistan): United Democratic Front (Urdu: قومی متحدہ محاذ ‎ ) was formed in Pakistan in 1973 in opposition to ruling Pakistan Peoples Party of Prime Minister Zulfikar Ali Bhutto.  This was a coalition of opposition parties in the National Assembly and Senate.

K. P. Mohanan: K. P. Mohanan (Malayalam: കെ.പി.  മോഹനൻ), is the former Kerala State Minister for Agriculture in United Democratic Front Cabinet from 18 May 2011.  He is the son of Kerala's former Minister Late Shri.  P. R. Kurup and Late Smt.  K.P. Leelavathy Amma; born at Puthoor near Panoor in Kannur district of Kerala on 3 March 1950.  He is the General Secretary of Socialist Janata (Democratic) Party (SJD) based in Kerala, India.  SJD is part of Congress-led United Democratic Front.  As a minister K. P. Mohanan has to handle portfolios of Agriculture, Soil Conservation, Soil Survey, Warehousing Corporation, Agricultural University, Animal Husbandry, Veterinary University, Printing and Stationery.

Zulfikar Ali Bhutto: Zulfikar Ali Bhutto (Urdu: ‎ ; Sindhi: ذوالفقار علي ڀُٽو‎ ) ] ) (5 January 1928 – 4 April 1979) was a Pakistani politician who served as Prime Minister of Pakistan from 1973 to 1977, and prior to that as the fourth President of Pakistan from 1971 to 1973.  He is revered by his followers in Pakistan as Quaid-i-Awam (Urdu: ‎ People's Leader).  He was also the founder of the Pakistan People's Party (PPP) and served as its chairman until his execution in 1979.

United Democratic Front (Kerala): The United Democratic Front (UDF) is an alliance of political parties in Kerala state, India, created by the prominent Indian National Congress (INC) party leader Shri.  K. Karunakaran in the 1970s.  Since its formation, the coalition has sustained itself on support from different social, caste and religious groups as a powerful bloc to take on the Communist Party of India (Marxist) (CPI (M)) led Left Democratic Front (LDF).  This alliance is led by the INC party in the state of Kerala.  In the 2016 Legislative assembly elections UDF just won 47 out of 140 seats and hence lost the power again to Left Democratic Front.  Later in 2016 august KC(M)Kerala Congress (M) left the alliance.

United Democratic Front (Botswana): The United Democratic Front (UDF) was a coalition of opposition parties in Botswana, formed ahead of the 1994 parliamentary election.  The UDF consisted of the MELS Movement of Botswana, the Botswana Workers Front and the Social Democratic Party.  UDF opposed both the ruling Botswana Democratic Party and opposition Botswana National Front.  No UDF candidate was able to get elected.

Supporting paragraphs: United Democratic Front (Pakistan) Zulfikar Ali Bhutto
Answer: Zulfikar Ali Bhutto