13. Which of the following best explains why the two DNA polymerase proteins that are held by the sliding clamp are oriented in the opposite directions? (A) The efficiency of replication is increased if the two DNA polymerases synthesize the template in the opposite directions (B) DNA polymerase is such a large protein complex that steric hindrance prevents both polymerases from following the replication fork (C) DNA polymerase can read only the template from 5' to 3' direction and the template strands are aligned in an anti-parallel direction (D) DNA polymerase can read only the template from 3' to 5' direction and the template strands are aligned in an anti-parallel direction (E) None of the above