Statements related to human insulin are given below. Which statement$(s)$ is/are correct about genetically engineered insulin?
$(a)$ Pro-hormone insulin contains an extra stretch of $C$-peptide.
$(b)$ $A$-peptide and $B$-peptide chains of insulin were produced separately in $E. coli$,extracted,and combined by creating disulfide bonds between them.
$(c)$ Insulin used for treating diabetes was extracted from cattle and pigs.
$(d)$ Pro-hormone insulin needs to be processed for converting into a mature and functional hormone.
$(e)$ Some patients develop allergic reactions to the foreign insulin.
Choose the most appropriate answer from the options given below:

• A
  $(b)$ only
• B
  $(c)$ and $(d)$ only
• C
  $(c), (d)$ and $(e)$ only
• D
  $(a), (b)$ and $(d)$ only