Triple

Target class: self-dual formulation of gravity
Context triple: [Plebański action for gravity, instanceOf, self-dual formulation of gravity]

• A. geometric theory of gravity chosen
  A geometric theory of gravity describes gravitational phenomena as manifestations of the curvature or structure of spacetime itself, rather than as a traditional force acting at a distance.
• B. electric–magnetic duality
  Electric–magnetic duality is a symmetry in certain physical theories that interchanges electric and magnetic fields or charges, often mapping a strongly coupled description of a system to a weakly coupled one while preserving its physical content.
• C. supergravity solution
  A supergravity solution is a specific configuration of fields (including the metric and superpartner fields) that satisfies the coupled equations of motion of a supergravity theory, often representing extended objects like branes or black holes in a higher-dimensional spacetime.
• D. formulation of cosmic censorship conjecture
  The formulation of the cosmic censorship conjecture is the theoretical class of principles proposing that singularities arising from gravitational collapse are always hidden within event horizons, preventing "naked" singularities from being observed and thus preserving the predictability of general relativity.
• E. supergravity background
  A supergravity background is a specific solution of supergravity field equations that defines a curved spacetime (often with fluxes and additional fields) in which strings or branes consistently propagate.
• F. None of above.