Which statement about enzymes that interact with DNA is TRUE?

A) E. coli DNA polymerase I is unusual in that it possesses only a 5' $\rightarrow$ 3' exonucleolytic activity.
B) Endonucleases degrade circular but not linear DNA molecules.
C) Exonucleases degrade DNA at a free end.
D) Many DNA polymerases have a proofreading 5' $\rightarrow$ 3' exonuclease.
E) Primases synthesize a short stretch of DNA to prime further synthesis.