Introduction:
Fixed time signals are an important part of traffic management system. They are used to regulate the flow of traffic and ensure safety on roads. The first time fixed time signals were used in a city was a significant event in the history of traffic management.

Answer:
The correct answer is option 'B', which is New York. The first time fixed time signals were used in a city was in New York in 1920. The signals were installed on a busy intersection in the city to regulate the flow of traffic. The signals were manually operated by a police officer who would change the signals based on the flow of traffic.

Importance of Fixed Time Signals:
Fixed time signals are an important part of traffic management system as they help to regulate the flow of traffic and ensure safety on roads. They are especially important in busy intersections where there is a high volume of traffic.

Evolution of Traffic Management System:
Since the first use of fixed time signals in New York, the traffic management system has evolved significantly. Today, traffic signals are automated and controlled by computers. They are equipped with sensors that can detect the flow of traffic and adjust the signal timings accordingly. This has made traffic management more efficient and effective.

Conclusion:
Fixed time signals were first used in New York in 1920 to regulate the flow of traffic. Since then, the traffic management system has evolved significantly and today, traffic signals are automated and controlled by computers. The use of fixed time signals has made traffic management more efficient and effective, ensuring safety on roads.

Answer is D