The correct answer is: a) Rural road connectivity.
The Pradhan Mantri Gram Sadak Yojana (PMGSY) is a government of India scheme launched in 2000 to provide connectivity to rural areas. The scheme aims to provide all-weather roads to all villages with a population of 500 or more and a road density of 100 km per 100 sq km.
The scheme has been successful in improving rural road connectivity. As of 2019, the scheme has constructed over 1.5 lakh km of roads and connected over 1.7 lakh villages. The scheme has also helped to reduce poverty and improve the quality of life in rural areas.
The other options are incorrect because they are not the focus of the PMGSY. Irrigation facilities, power supply in villages, and sanitation are all important issues, but they are not the primary focus of the PMGSY.
Irrigation facilities are important for agricultural production. Power supply in villages is important for economic development. Sanitation is important for public health. However, these issues are not the primary focus of the PMGSY. The primary focus of the PMGSY is to improve rural road connectivity.