The pathogenic effects of prions are thought to result from:

A) Viroids acting as a template for the synthesis of the prion proteins
B) Aberrant forms of mammalian cellular proteins that convert more mammalian cellular proteins to aberrant forms, leading to a clumping of the proteins, eventually killing the cell.
C) Prions converting viroids into abberant proteins that kill the cell
D) All of these
E) None of these