28. Emma wants to analyze the sequence of the following peptide "SMALLCATSNICKASHIRT". She uses several agents to treat the sample. Which of the following description is correct?(A) If she uses trypsin, she could get the peptide "KASHI".(B) If she uses phenylisothiocynate, she could only know that the first residue is "S".(C) If she uses trypsin, she could get the peptide "SMALLCATSNICK".(D) In order to know whether this peptide has disulfide bond, she can treat the sample with or without cyanogen bromide (CNBr) before trypsin digestion and compare the result. If the treatment of cyanogen bromide makes no difference, the result suggests no disulfide bond formation in this peptide.(E) If she uses pepsin, she can get the peptide "ATSNICKASHIRT",