Explanations:The Delhi Metro is a rapid transit system that serves the National Capital Region of Delhi, India. It is a crucial part of the city's transportation infrastructure, providing a reliable and efficient means of travel for millions of commuters daily. The nickname "life line of Delhi" is used to emphasize the essential role the Metro plays in the daily lives of the city's residents and visitors.
The term "life line" is a metaphor that highlights the importance of the Delhi Metro in facilitating the smooth functioning of the city. It underscores the Metro's significance in reducing traffic congestion, providing a clean and efficient mode of transport, and connecting various parts of the city. The Metro system has become an indispensable part of the city's daily life, making it a lifeline for many who rely on it for commuting to work, school, and other activities.
Other options like "land line" and "water line" are not appropriate in this context. "Land line" typically refers to fixed telephone lines, which are unrelated to the Metro system. "Water line" is associated with water supply systems, which again is not relevant to the Metro. The term "heart of Delhi" is more commonly used to describe the central business district or the historical center of the city, not the Metro system.
Understanding the significance of the Delhi Metro as the "life line of Delhi" is important for anyone studying the city's infrastructure and transportation systems. It reflects the Metro's role in the city's daily life and its importance in the context of urban planning and development.