Triple

Target class: classical modular function
Context triple: [modular j-invariant, instanceOf, classical modular function]

• A. endomorphism of modular forms space
  An endomorphism of a modular forms space is a linear self-map of a given space of modular forms (typically of fixed weight, level, and character) that sends each modular form in the space to another modular form in the same space.
• B. L-function
  An L-function is a complex analytic function, typically expressed as a Dirichlet series with an Euler product, that encodes deep arithmetic information about objects such as numbers, fields, or algebraic varieties.
• C. arithmetical function
  An arithmetical function is a function defined on the positive integers that assigns to each integer a (usually complex or real) value, often encoding number-theoretic properties such as divisors, primes, or multiplicative structure.
• D. special function chosen
  A special function is a mathematically well-studied function, often arising as a solution to differential equations or integrals, that has established names, properties, and applications across many areas of science and engineering.
• E. classical invariant
  A classical invariant is a quantity or property associated with a mathematical object that remains unchanged under a specified group of classical transformations, such as rotations, translations, or linear changes of coordinates.
• F. None of above.