AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.
Answer: (B)
The vast level land, high population density, and rich agricultural resources of the northern plains provided favourable conditions for developing the most extensive railway network in India.
Option B is correct because the northern plains offered flat terrain (easy to lay tracks), dense population (high passenger demand), and agricultural produce requiring transportation. Options A, C, and D are either factually incorrect or not supported by the textbook. Examiners expect students to identify the geographic and economic factors — level land, population, and agriculture — as the key reasons.