c. a phosphodiester bond between the 3' and 5' hydroxyl groups of neighboring sugars
Explanation:
Phosphodiester bond is the bond which is formed between the hydroxyl group of one nucleotide to the phosphate group of the another nucleotide. These are ester bonds. These bonds are central to all the life which is in existence on Earth. These bonds forms the backbone of the strands of the nucleic acid.
The bond is formed by the linkage of 3' carbon atom of one of the sugar unit to the 5' carbon atom of the another succeeding sugar unit.
<u>Hence, the answer is:- c. a phosphodiester bond between the 3' and 5' hydroxyl groups of neighboring sugars</u>
