Read the paragraph given below and answer the question.
Insulin used for diabetes was earlier extracted from slaughtered cattle and pigs. Insulin from an animal source, though caused some patients to develop allergy or other type of reactions. Insulin consists of two short polypeptide chains: chain A and chain B, that are linked bridges. In mammals, including human, insulin is synthesised as a pro-hormone.
Identify the correct statements.
(A) Insulin was earlier extracted from the liver of slaughtered animals.
(B) Eli Lilly, an American company is producing insulin using r-DNA technique.
(C) Some diabetics developed allergy with the animal sourced insulin.
(D) Pro-insulin can control diabetes.
Choose the correct answer from the options given below :

1. A (A) and (B) Only
2. B (B) and (D) Only
3. C (B) and (C) Only
4. D (A) and (D) Only