Which Is True of Klenow Fragments

Which is true of Klenow fragments?

A) They are the result of removal of the proofreading domain of a prokaryotic DNA polymerase
B) They result from treatment of ligase with a protease
C) Protease treatment of DNA polymerase III can give rise to Klenow fragments
D) They are another name for Okazaki fragments
E) An important part of the replisome, they block nucleophilic attack on the phosphodiester backbone.