87395
According to Walter Gratzer , the study of nutrition probably began during the 6th century BC .
 person: Walter Gratzer
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: Walter Gratzer 
Answer:
 person: Walter Gratzer