the main, or central, idea of the passage is to replace an inefficient emergency call system, the u.s…

the main, or central, idea of the passage is to replace an inefficient emergency call system, the u.s. government instituted nationwide 911 service. how does the detail in bold develop the main idea? prior to 1968, the united states did not have a nationwide phone number for emergency assistance; instead, emergency numbers varied from region to region. when people required urgent help from the police or the fire department, they had to either call the operator or dial their local services directly. concerned about the dangerous inefficiency of this system, the federal government decided to establish a single emergency number that could be used throughout the country. the telecom company at&t proposed that the code be 911, a sequence that was easily remembered and not already in use as an area code or service code. this proposal was accepted, and the first 911 call was made by alabama senator rankin fite on february 16, 1968. it challenges the accepted wisdom about emergency services. it describes an improved way for the emergency system to function. it provides background information about the old emergency system.
Answer
Brief Explanations:
The bold - faced text describes the pre - 1968 emergency system where numbers varied by region and people had to call operator or local services. This gives context about the old, inefficient system that the 911 service aimed to replace.
Answer:
It provides background information about the old emergency system.