Cost advantage of recombinant insulin

Steps:

• Recombinant DNA technology inserts human insulin genes into bacteria for mass production.
• Bacteria culture yields large quantities of insulin efficiently without animal sourcing.
• Animal insulin extraction involves costly harvesting and purification from pancreases.
• This makes bacterial insulin cheaper overall for patients.

Why D is correct:

• Recombinant production scales via bacterial replication, reducing costs per unit compared to labor-intensive animal extraction.

Why the others are wrong:

• A: Insulin treats existing diabetes but does not prevent its development.
• B: Insulin replacement therapy does not regenerate pancreatic cells.
• C: Human insulin causes fewer allergic reactions and side effects than animal-derived versions.

Final answer: D