15. Which of the following lacks 3'-5' exonuclease activity?
A.Short fragment of DNA polymerase I
B.Taq DNA polymerase
C.T4 DNA ligase
D.All of the above

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16. The synthesis of DNA by DNA polymerase occurs in the
A.3' to 5' direction
B.5' to 5' direction
C.5' to 3' direction
D.3' to 3' direction

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