38348
Confirmed use of biological warfare by a nation state has not occurred since 1945 , and chemical warfare has been used only a few times ( the latest known confrontation in which it was utilized being the Syrian Civil War ) .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
 None