If Organization A trusts Organization B and Organization B trusts Organization C, then Organization A trusts Organization C. Which of the following PKI concepts is this describing?

Transitive trust describes how trust flows along a chain of relationships without requiring a direct trust agreement between every pair. In PKI, this underpins cross-certification and certificate chain validation, where a relying party trusts an end-entity certificate because it can trace a valid chain back through intermediate CAs to a trusted root.

Public key trust refers to the binding of a public key to an identity via a certificate, not to how trust propagates between organizations.

Certificate authority trust describes the trust placed in a specific CA to issue valid certificates, not the chaining of trust across multiple organizations.

Domain level trust is a Windows Active Directory concept for intra-forest or inter-forest trust relationships and does not describe the general PKI chain-of-trust model.