Final answer:
The correct option is D) growth hormone. The amino acid-based hormone that uses the direct gene activation method is growth hormone (GH).
Step-by-step explanation:
The amino acid-based hormone that uses the direct gene activation method is growth hormone (GH). Growth hormone, produced by the anterior portion of the pituitary gland, accelerates the rate of protein synthesis. It has both direct and indirect mechanisms of action.
Directly, it stimulates triglyceride breakdown and glycogen breakdown, resulting in increased blood glucose levels. Indirectly, it mediates its effects through insulin-like growth factors (IGFs).