Recently, India signed a deal known as 'Action Plan for Prioritization and Implementation of Cooperation Areas in the Nuclear Field' with which of the following countries?

Option (b) is correct as India and Russia signed this Action Plan during the 19th India-Russia Annual Bilateral Summit in 2018 to facilitate the construction of six nuclear power units at a new site in India. While the United States (d) is a significant nuclear partner following the 2008 Civil Nuclear Deal, this specific "Action Plan" is a distinct component of the Indo-Russian strategic energy roadmap. The core concept tested is India’s bilateral strategic partnerships and international civil nuclear cooperation.