Which of the following statements about DNA synthesis is true?

Question: Part B Which of the following statements about DNA synthesis is true?

1. Primers are short sequences that allow the initiation of DNA synthesis.
2. As DNA polymerase moves along the template strand, each new nucleotide provides a 5′ hydroxyl group for the next reaction to occur
3. DNA polymerase adds dNTP monomers in the 3′ to 5′ direction.
4. Nucleotides are added in a random fashion to single-stranded DNA

First question (Part B):

The answer will be primers are short sequences that allow the initiation of DNA synthesis (First option).

Explanation:

Each nucleotide provides a 3′ hydroxyl group for the next reaction to occur. So, we can ignore second option. DNA polymerase add dNTP in the 5′ to 3′ direction. So, we can ignore third option. Nucleotides are not added in the random fashion, instead they are added depending on the nucleotides of template strand. So, we can ignore last option. Primers are short sequences & provide a free 3′-OH group to which DNA polymerase can add first dNTP to begin DNA synthesis. So, correct answer will be first option.