Given the task definition and input, reply with output. In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.

Question: How long in hours does it take to create cyclic peptides? Passage:Split-intein circular ligation of peptides and proteins (SICLOPPS) is a biotechnology technique that permits the creation of cyclic peptides. These peptides are produced by ribosomal protein synthesis, followed by an intein-like event that splices the protein into a loop. By contrast with the nonribosomal peptide synthetases that produces some cyclic peptides like gramicidin S, SICLOPPS offers the advantage that the peptides' structure can be encoded by DNA in a simple manner according to the genetic code, but for this reason it imposes limitations on the types of amino acids incorporated that are comparable to those that apply to ordinary proteins. As implemented there is also some constraint on the peptide sequence of the cyclic sequence; for example, libraries may use the sequence SGXX..XXPL to increase the efficiency of circularization of the peptide. SICLOPPS is frequently used with a library of randomized DNA sequence that permits the simultaneous production and screening of large numbers of constructs at once, followed by the recovery of the DNA sequences responsible for the activity of the clone of interest.
 Links: a. Gramicidin S b. Cyclic peptide c. Protein d. Cyclic peptide

b