Read the given passage carefully and answer the following questions.

The process of development of the tribal area of Bharmaur started in the 1970s when Gaddis were included among 'scheduled tribes'. The Fifth Five-Year Plan, the tribal sub-plan was introduced in 1974 and Bharmaur was designated as one of the five Integrated Tribal Development Projects (ITDP) in Himachal Pradesh. This area development plan was aimed at improving the quality of life of the Gaddis and narrowing the gap in the level of development between Bharmaur and other areas of Himachal Pradesh. This plan laid the highest priority on development of transport and communications, agriculture and allied activities, and social and community services. The most significant contribution of tribal sub-plan in Bharmaur region is the development of infrastructure in terms of schools, healthcare facilities, potable water, roads, communications and electricity. But the villages located along the river Ravi in Holi and Khani areas are the main beneficiaries of infrastructural development. The remote villages in Tundah and Kugti areas still do not have sufficient infrastructure. The social benefits derived from ITDP include tremendous increase in literacy rate, improvement in sex ratio and decline in child marriage. The female literacy rate in the region increased from 1.88 percent in 1971 to 65 percent in 2011. The difference between males and females in literacy level i.e. gender inequality, has also declined. Traditionally, the Gaddis had a subsistence agricultural-cum-pastoral economy, having an emphasis on food grains and livestock production. But during the last three decades of the twentieth century, the cultivation of pulses and other cash crops has increased in Bharmaur region. But crop cultivation is still done with traditional technology.

What is the most significant contribution of the Tribal sub-plan in the Bharmaur region?

Development of Infrastructure in terms of schools, healthcare facilities, potable water, roads etc.

The correct answer is Option (3) → Development of Infrastructure in terms of schools, healthcare facilities, potable water, roads etc.

The passage clearly states that the most significant contribution of the Tribal Sub-Plan in the Bharmaur region is the development of infrastructure, including schools, healthcare facilities, potable water, roads, communication, and electricity. This infrastructural development was central to improving the quality of life for the Gaddi tribe.