<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:An investigator is studying the effect of chromatin structure on gene regulation. The investigator isolates a class of proteins that compact DNA by serving as spools upon which DNA winds around. These proteins are most likely rich in which of the following compounds?? A: Phosphate, B: Proline and alanine, C: Heparan sulfate, D: Lysine and arginine, E: Disulfide-bonded cysteine,  <response>: This question is asking about proteins that compact DNA by serving as spools that DNA winds around. The key information here is that these proteins compact and wind DNA around them. Proteins that can compact and wind DNA typically contain a large number of positively charged amino acids like lysine and arginine. The positively charged side chains of these amino acids can interact with the negatively charged DNA backbone and help compact the DNA.D: Lysine and arginine 