What advantage can the mid Hills pushpalal Highway provides​

The mid hill play an important role for the communication between the plains and the extreme hilly areas.

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In addition to this there is wide amount of fertile region in the mid hilly area and as a result of this wide variety of rocks are found there. Also there is also plenty of rainfall and white growth of trees are found which prevent soil erosion. It helps in the transportation of goods and essential services to the people who are living in the hilly region and mountains also they are important for the purpose of  development of all sectors of land

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the answer is d.index