Which group of organic compounds stores genetic information?

I got D, C, A, B, C, B, D, C. 

C (proteins) instead of D (nucleic acids) because if you look at a nucleic acid structure, you'll see that sulfur is not found in it. Sulfur is found in two amino acids (methionine and cysteine), which means it could be found in proteins since amino acids build proteins

Covalent bond is the correct answer