Definition of Relying-Party Trust

While preparing for the 70-412 exam, I found this exam tip in Exam Ref 70-412.

A relying-party trust means that a specific claims-provider trusts a specific relying party.

Isn't it the relying party should trust claims-provider? I mean claims-provider claims that some information it provided is true, and relying party relies on that information and trusts.

Thank you.