The correct answer is B) They were killed in a military coup.
What happened to Ngo Dinh Diem and his brother Nhu was that they were killed in a military coup.
South Vietnam had many problems in the 1960s. Social, military, and political conflicts divided the country. On November 2, 1963, South Vietnamese military troops overthrew the government of Ngo Dinh Diem and arrested him and his brother. The following day both men were assassinated, starting a more volatile and tense period in South Vietnam.
