Which sector was given the main emphasis in the second Five-Year Plan?

Correct option is D

The second Five-Year Plan of India, which covered the period from 1956 to 1961, gave the main emphasis on industrialization. The primary focus of the plan was to develop heavy industries such as steel, chemicals, and machinery, and to strengthen the infrastructure necessary for their growth.
The plan aimed to achieve a target of 25% increase in national income over the five-year period. The second Five-Year Plan also focused on increasing agricultural productivity, developing irrigation facilities, and improving the social services sector.