Genetically engineered insulin contains A-peptide and B-peptide chains of insulin that are produced separately in E.coli before being extracted and combined via a disulphide bond. Hence, is the appropriate answer.

Statement is incorrect as genetically engineered insulin does not have an extra stretch of C- peptide.

Statement is incorrect as insulin obtained from cattle and pigs is not genetically engineered insulin.

Statement is incorrect because conversion of pro-insulin to insulin is not required during production of insulin by genetic engineering as A-peptide and B-peptide chains are produced separately.

Statement (e) is incorrect as allergic reactions to insulin are mostly seen when the insulin is obtained from animals.