Evaluating hormone functions in blood glucose regulation

Steps:

• Statement 1: Insulin is produced in the pancreas (correct), but it decreases blood glucose by promoting uptake into cells, not increases it.
• Statement 2: Adrenaline raises blood glucose by stimulating glycogen breakdown and gluconeogenesis, not lowers it.
• Statement 3: Insulin is correct; it treats diabetes mellitus by replacing deficient hormone to lower elevated blood glucose.
• Conclusion: Only statement 3 is accurate, so option D.

Why D is correct:

• Insulin therapy directly addresses diabetes mellitus by mimicking the hormone's role in reducing hyperglycemia, per endocrine physiology.

Why the others are wrong:

• A includes incorrect statements 1 and 2 on insulin and adrenaline effects.
• B includes both false statements 1 and 2.
• C selects only false statement 2 about adrenaline.

Final answer: D