79599
During President John F. Kennedy 's term , while McNamara was Secretary of Defense , America 's troops in South Vietnam increased from 900 to 16,000 advisers , who were not supposed to engage in combat but rather to train the Army of the Republic of Vietnam ( ARVN ) .
 John F. Kennedy, McNamara, Defense, America, South Vietnam, Army of the Republic of Vietnam, ARVN
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 John F. Kennedy, McNamara, Defense, America, South Vietnam, Army of the Republic of Vietnam, ARVN