Which Statement Below Best Describes the Molecular Difference Between Free

Multiple Choice

Which statement below best describes the molecular difference between free PSA (fPSA) and complex PSA (cPSA) ?

A) Free PSA is bound by compounds such as ACT, PCI, API, or AMG.
B) Free PSA is an active form that can complex with protease inhibitors.
C) Free PSA is not bound by compounds such as ACT, PCI, API, or AMG.
D) Free PSA cannot be detected in serum, whereas complex PSA can.