The moving car observer method is a procedure used in traffic engineering to find the traffic flow of a traffic stream. It involves observing the movement of cars from a moving vehicle along a road section and making relevant observations and measurements. This method is commonly used to estimate the traffic flow rate, which is the number of vehicles passing a given point on the road per unit of time.

**Procedure of Moving Car Observer Method:**

1. **Selection of Observation Point:** The first step in the moving car observer method is to select an appropriate observation point on the road section. This point should be representative of the overall traffic flow and should be easily accessible from a moving vehicle.

2. **Observation Setup:** Once the observation point is selected, the observer sets up the necessary equipment in the moving vehicle. This may include a video camera, a speedometer, and a measuring device to count the number of vehicles passing the observation point.

3. **Data Collection:** The observer then starts the vehicle and drives along the road section while recording the movement of vehicles using the video camera. Simultaneously, the speedometer is used to measure the speed of the vehicle. The observer also counts the number of vehicles passing the observation point.

4. **Data Analysis:** After the observation is complete, the recorded data is analyzed to determine the traffic flow rate. This involves counting the number of vehicles passing the observation point in a given time period and dividing it by the duration of the observation.

5. **Traffic Flow Estimation:** Based on the data collected and analyzed, the traffic flow rate can be estimated for the road section. This information is useful for traffic engineers to assess the level of congestion, plan road improvements, and optimize traffic signal timings.

**Importance and Applications of Moving Car Observer Method:**

The moving car observer method is an important tool in traffic engineering as it provides valuable information about the traffic flow on a road section. It has several applications, including:

- Estimating the traffic capacity of a road section: By determining the traffic flow rate, the moving car observer method can be used to estimate the maximum number of vehicles that can pass through a road section in a given time period. This information is crucial for designing and planning road infrastructure.

- Carrying out origin-destination studies: The movement of vehicles observed using this method can be used to understand the origin and destination patterns of traffic. This information is useful for planning transportation systems and optimizing routes.

- Identifying accident-prone locations on highways: The moving car observer method can help identify locations on highways where accidents are more likely to occur. By analyzing the data collected, traffic engineers can identify factors contributing to accidents and implement appropriate safety measures.

In conclusion, the moving car observer method is a procedure used in traffic engineering to find the traffic flow of a traffic stream. It involves observing the movement of vehicles from a moving vehicle and analyzing the collected data to estimate the traffic flow rate. This method is important for various applications, including estimating traffic capacity, conducting origin-destination studies, and identifying accident-prone locations on highways.

B option is correct