Question: Name the President of Argentina who was overthrown during the 1976 coup d'état, which disrupted a planned guerrilla operation by the PVP of Uruguay which included exiles in Argentina?
Context: The "Dirty War" (Spanish: "Guerra Sucia" ), was the name used by the Argentine Military Government for a period of state terrorism in Argentina from roughly 1974 to 1983 (some sources date the beginning to 1969), during which military and security forces and right-wing death squads in the form of the Argentine Anticommunist Alliance (Triple A) hunted down and killed left-wing guerrillas, political dissidents, and anyone believed to be associated with socialism.  About 30,000 people disappeared, many of which were impossible to be formally reported due to the nature of the issue: state terrorism.  The targets were left-wing activists, guerrillas and militants, trade unionists, students, journalists and Marxists and Peronist guerrillas and their support network in the Montoneros believed to be 150,000-250,000-strong and 60,000-strong in the ERP, as well as alleged sympathizers.  Some 10,000 of the "disappeared" were guerrillas of the Montoneros (MPM) and the Marxist People's Revolutionary Army (ERP) although the lowest estimate is that the Montoneros and ERP had a combined strength of 5,000.  The "disappeared" included those thought to be a political or ideological threat to the military junta, even vaguely, and they were killed in an attempt by the junta to silence the opposition and break the determination of the guerrillas.  The worst repression reportedly occurred after the guerillas were largely defeated in 1977, when the church, labor unions, artists, intellectuals and university students and professors were targeted.  Although the Montoneros reported having carried out some 600 armed attacks in 1977, the guerrilla threat had greatly declined.  The junta justified this mass terror by exaggerating the guerrilla threat, and even staged attacks to be blamed on guerillas and used frozen dead bodies of guerilla fighters that had been kept in storage for this purpose.  In late 1979, Amnesty International accused the Videla military government of being responsible for the disappearance of 15,000 to 20,000 Argentine citizens since the 1976 coup.  That year, a special study by the New York City Bar concluded that around 10,000 Argentines had disappeared since the coup.  According to "Registro Unificado de Víctimas del Terrorismo de Estado" (Ruvte), 662 were disappeared under the presidency of Isabel Perón and 6,348 were disappeared during the military dictatorship. The 1976 Argentine coup d'état was a right-wing coup that overthrew Isabel Perón as President of Argentina on 24 March 1976.  A military junta was installed to replace her; this was headed by General Jorge Rafael Videla, Admiral Emilio Eduardo Massera and Brigadier-General Orlando Ramón Agosti.  The junta took the official name of "National Reorganization Process", and remained in power until December 10, 1983. The 1945 Venezuelan coup d'état took place on 18 October 1945, when the dictator Isaías Medina Angarita was overthrown by a combination of a military rebellion and a popular movement led by Democratic Action.  The coup led to a three-year period of government known as El Trienio Adeco, which saw the first democratic elections in Venezuelan history, beginning with the Venezuelan Constituent Assembly election, 1946.  The Venezuelan general election, 1947 saw Democratic Action formally elected to office (with Rómulo Gallegos as President, replacing interim President Rómulo Betancourt), but it was removed from office shortly after in the 1948 Venezuelan coup d'état. Mir Ahmad Shah Rizwani (d. 1978) was an Afghan Islamist intellectual and military general, who led a 1976 coup against the Afghan government, and was later executed after the 1978 communist takeover of the country.  Due to his prominence and influence as a scholar, he had been brought into the government fold and given the title of "Firqa Meshir", chief of the army.  Rizwani was a follower of Islamic scholar Muhammad Atta-ullah Faizani, and headed his own Islamist group, mainly composed of army personnel, called Qiyam-i Islami (Islamic Uprising), which plotted an abortive 1976 coup against the government of President Mohammed Daoud Khan.  The coup was preempted; Rizwani and 50 of his associates were arrested on 9 December 1976, and Rizwani executed in 1978 following the communist takeover. Jean-Bertrand Aristide (born 15 July 1953) is a Haitian priest and politician who became Haiti's first democratically elected president.  A proponent of liberation theology, Aristide was appointed to a Roman Catholic parish in Port-au-Prince in 1982 after completing his studies to become a priest of the Salesian order.  He became a focal point for the pro-democracy movement first under Jean-Claude "Baby Doc" Duvalier and then under the military transition regime which followed.  He won the Haitian general election between 1990 and 1991, with 67% of the vote and was briefly president of Haiti, until a September 1991 military coup.  The coup regime collapsed in 1994 under US pressure and threat of force (Operation Uphold Democracy).  Aristide was then president again from 1994 to 1996 and from 2001 to 2004.  However, Aristide was ousted in a 2004 coup d'état, in which one of his former soldiers participated.  He accused the United States of orchestrating the coup d'état against him with support from Jamaican prime minister P. J. Patterson, among others.  Aristide was later forced into exile in the Central African Republic and South Africa.  He finally returned to Haiti in 2011 after seven years in exile. The 1996 Burundian coup d'état was a military coup d'état that took place in Burundi on 25 July 1996.  In the midst of the Burundi Civil War, former president Pierre Buyoya (a Tutsi) deposed Hutu President Sylvestre Ntibantunganya.  According to Amnesty International, in the weeks following the coup, more than 6,000 people were killed in the country.  This was Buyoya's second successful coup, having overthrown Jean-Baptiste Bagaza in 1987. The 1973 Rwandan coup d'état, also known as the Coup d'état of 5 July (French: "Coup d'état du 5 Juillet" ), was a military coup staged by Juvénal Habyarimana against incumbent president Grégoire Kayibanda in the Republic of Rwanda.  The coup took place on 5 July 1973 and was bloodless. The Partido por la Victoria del Pueblo, also known as the Party for the Victory of the People or People's Victory Party (PVP), is a political organization in Uruguay.  Its military wing is known as OPR-33.  The leftist group began under an anarcho-syndicalist philosophy and was overshadowed by Tupamaros in Uruguay.  The Party grew in strength among exiles in Argentina, both in followers and money, with $10 million from the successful ransom for a kidnapped businessman.  Their planned an guerrilla operation to reclaim its place in Uruguay went awry with the surprise 1976 Argentine coup d'état.  Several days after the coup, three PVP members were arrested while attempting to cross back into Uruguay.  The arrests continued through the other group members in Argentina, dozens in total, including its leaders, in concert with Uruguay security forces. The 1963 Togolese coup d'état was a military coup that occurred in the country of Togo on 13 January 1963.  The coup leaders (notably Emmanuel Bodjolle, Étienne Eyadéma and Kléber Dadjo) took over government buildings, arrested most of the cabinet, and assassinated Togo's first President, Sylvanus Olympio outside the American embassy in Lomé.  The coup leaders quickly brought Nicolas Grunitzky and Antoine Meatchi, both of whom were exiled political opponents of Olympio, together to form a new government.  While the government of Ghana and its President Kwame Nkrumah were implicated in the coup and assassination of Olympio, full investigation was never completed and the international outcry eventually died down.  The event was important as the first coup d'état in the French and British colonies of Africa that achieved independence in the 1950s and 1960s, and Olympio is remembered as one of the first heads of state to be assassinated during a military coup in Africa. The Bulgarian coup d'état of 1944, also known as the 9 September coup d'état (Bulgarian: Деветосептемврийски преврат , "Devetoseptemvriyski prevrat") and called in pre-1989 Bulgaria the National Uprising of 9 September or the Socialist Revolution of 9 September, was a change in the Kingdom of Bulgaria's administration and government carried out on the eve of 9 September 1944.  The government of Prime Minister Konstantin Muraviev was overthrown and replaced with a government of the Fatherland Front led by Kimon Georgiev.  While the Soviet Union supported the coup, their forces (the Third Ukrainian Front) were not directly involved in it, as they had only occupied northeastern Bulgaria at this point.  Following that date, large-scale political, economic and social changes were introduced to the country, with Bulgaria quitting the Axis and coming into the Soviet sphere of influence.
Answer: Isabel Perón