Final answer:
A phosphodiester bond is represented by the letter B, a glycosidic bond is represented by the letter D, and a hydrogen bond is represented by the letter C.
Step-by-step explanation:
A phosphodiester bond is represented by the letter B. It is a covalent bond that forms between nucleotides in DNA and RNA. Phosphodiester bonds are formed through dehydration synthesis reactions, where a hydroxyl group is removed from the 3' carbon of one nucleotide and a hydrogen atom is removed from the hydroxyl group attached to the 5' carbon of another nucleotide. Water is produced and a phosphodiester bond is formed.
A glycosidic bond is represented by the letter D. It is a covalent bond that forms between monosaccharides to create polysaccharides. For example, glucose and galactose form a glycosidic bond to create the disaccharide lactose.
A hydrogen bond is represented by the letter C. It is a weak bond that forms between molecules with polar covalent bonds, like water. Hydrogen bonds play an important role in the structure and function of biological molecules, including DNA and proteins.