A hydrogen bond is the electromagnetic attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. This is not a sharing of electrons, as in a covalent bond. Instead, this is an attraction between the positive and negative poles of charged atoms.
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Answer:
RNA primer
Explanation:
the DNA polymerase can't synthesize DNA without an 3' ending, the primase enzyme synthesize an RNA primer that brings to the DNA polymerase the 3' spot so she can finally starts the new DNA chain.
C. Hardness is the answer