## **Core Concept**
The question tests the ability to identify a peptide hormone from a list of options. Peptide hormones are a class of hormones composed of short chains of amino acids, as opposed to steroid hormones which are derived from cholesterol. They are typically produced by glands and play crucial roles in regulating various physiological processes.

## **Why the Correct Answer is Right**
Thyroid-stimulating hormone (TSH) is a peptide hormone produced by the anterior pituitary gland. It regulates the endocrine function of the thyroid gland by stimulating it to produce thyroid hormones, primarily thyroxine (T4) and triiodothyronine (T3). TSH is indeed a peptide hormone, consisting of two subunits (alpha and beta), which is characteristic of its classification.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is not provided, but typically, incorrect options might include steroid hormones, amino acid derivatives, or other types of hormones not classified as peptides.
- **Option B:** Similarly, without the specific content of Option B, we can infer that any non-peptide hormone (like insulin is a peptide, so something like a steroid or amine hormone) would be incorrect.
- **Option C:** This would also be incorrect based on the same reasoning; if it's not a peptide hormone, it doesn't fit the criteria.
- **Option D:** Incorrect for the same reason; it does not represent a peptide hormone.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that peptide hormones are water-soluble and cannot diffuse through the cell membrane, so they exert their effects by binding to specific receptors on the cell surface. This is in contrast to steroid hormones, which are lipid-soluble and can diffuse through the cell membrane to exert their effects intracellularly.

## **Correct Answer: C. TSH (Thyroid-Stimulating Hormone).**