4784
A survey team led by David Thompson in 1824 mapped the lake and found four possibilities , but did not conclusively declare one location .
 person: David Thompson
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
 Entities: David Thompson 
Answer:
 person: David Thompson