Triple

Target class: cohomological invariant
Context triple: [Shafarevich group of a torus, instanceOf, cohomological invariant]

• A. cohomological invariant chosen
  A cohomological invariant is a rule that assigns to each object in a given class (such as algebraic varieties, groups, or topological spaces) an element of a cohomology group in a way that is functorial and captures structural or classification information about those objects.
• B. homological invariant
  A homological invariant is a quantity or structure derived from homology theory that remains unchanged under specified transformations, used to distinguish and classify mathematical objects up to an appropriate notion of equivalence.
• C. cohomology theory
  A cohomology theory is a functorial assignment of graded algebraic invariants to topological spaces (or other mathematical objects) that encodes global structural and obstruction information via axioms such as exactness and homotopy invariance.
• D. object in invariant theory
  An object in invariant theory is a mathematical entity, such as a vector space, polynomial ring, or group action, whose structure and symmetries are studied through the functions or quantities that remain unchanged under a specified group of transformations.
• E. result in equivariant cohomology
  A result in equivariant cohomology is a theorem or statement describing how cohomological invariants behave under a group action, typically relating equivariant cohomology groups to ordinary cohomology or geometric data of the action.
• F. None of above.