The correct option is 3 and 4 only because District Rural Development Agencies (DRDAs) primarily focus on coordinating and implementing anti-poverty programs at the local level, ensuring that various government departments and sectors work together effectively. They are responsible for monitoring the allocation and utilization of funds designated for these programs, thus enhancing accountability and efficiency in poverty alleviation efforts. While DRDAs do play a role in the implementation of poverty alleviation schemes, they do not function as Panchayati Raj Institutions per se nor conduct specific scientific studies on poverty; instead, their main purpose is to facilitate and streamline existing programs to combat rural poverty.