**Core Concept**
Amine hormones are a class of hormones that are derived from amino acids and contain an amine group (-NH2). They are synthesized from the amino acid tyrosine and are characterized by their ability to cross the blood-brain barrier.

**Why the Correct Answer is Right**
T4 (thyroxine) is an amine hormone because it is synthesized from the amino acid tyrosine. It is a derivative of the amino acid tyrosine, which is converted into diiodotyrosine (DIT) and then coupled to form T4. T4 is then iodinated to form its active form. As an amine hormone, T4 can cross the blood-brain barrier and has widespread effects on metabolism and development.

**Why Each Wrong Option is Incorrect**
**Option A:** TSH (thyroid-stimulating hormone) is a peptide hormone, not an amine hormone. It is produced by the anterior pituitary gland and stimulates the release of T4 from the thyroid gland.

**Option C:** Insulin is a peptide hormone produced by the beta cells of the pancreas. It plays a critical role in glucose metabolism but is not an amine hormone.

**Option D:** FSH (follicle-stimulating hormone) is a peptide hormone produced by the anterior pituitary gland. It is involved in the regulation of reproductive processes but is not an amine hormone.

**Clinical Pearl / High-Yield Fact**
Amine hormones, such as T4, are often referred to as "lipid-soluble" hormones due to their ability to cross the blood-brain barrier. This property allows them to have widespread effects on metabolism and development.

**Correct Answer:**
✓ Correct Answer: B. T4