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One of the longest serving producers with the BBC Natural History Unit ( 1957-1987 ) , and the writer and presenter/narrator of many of the programmes he produced , he was also been prominent in the development of the ethics of natural history broadcasting and the encouragement of new entrants into the field .
 organization: BBC
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: BBC 
Answer:
 organization: BBC