71796
Scottish inventor John Logie Baird demonstrated the world 's first color transmission on 3 July 1928 , using scanning discs at the transmitting and receiving ends with three spirals of apertures , each spiral with filters of a different primary color ; and three light sources at the receiving end , with a commutator to alternate their illumination .
 person: John Logie Baird
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: John Logie Baird 
Answer:
 person: John Logie Baird