376227
This causes blocked calls or dropped call s. However , it can also apply to landline phones , in which not enough trunking telephone circuit s are available into and out of any given telephone exchange or equivalent switching office at any level of the public switched telephone network ( PSTN ) .
 None
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:  
Answer:
 None