Answer:
there must be a pre-existing chain of nucleotides
Explanation:
So RNA primers are used for initiation of new DNA chains.
RNA primer is short piece of RNA, synthesised at the end of the new strand with the help of DNA specific RNA polymerase enzyme called primase and primers provide free -OH for DNA polymerase to start polymersing. leading template strand requires primer only ones. But lagging template strand requires many primers. Once primer is ready DNA Pol(III) will come & start adding deoxyribonucleotide to the -OH of primer by complementary basepairing. Two nucleotides link each other by phosphodiester bond. The daughter DNA for template is synthesised continuously, Therefore called leading strand. DNA polymeraseIII has Exonuclease activityIt can add nucleotides in the direction. Replication is discontinuous on the other template with polarity because only a short segment of DNA strand can be built in direction due to exposure of a small stretch of template at one time.
Please mark as brainlest.