27570
The MACOM for the 551st is ( TRADOC ) and they fall directly under the 15th Regimental Signal Brigade .
 organization: 551st; organization: 15th Regimental Signal Brigade
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: 551st, 15th Regimental Signal Brigade 
Answer:
 organization: 551st; organization: 15th Regimental Signal Brigade