• A A mechanism of digitally "signing" the information exchanged between applications/systems.
  • B A mechanism which enables using single physical "signature" to do all banking transactions!
  • C A mechanism that enables a user to sign-in/login/authenticate to an application/system with their credentials only once, and then seamlessly access other applications/systems available in the same domain of trust (e.g. intranet portal of an organization),
  • D None of the above options.