**Core Concept**
A mass in the sella turcica typically arises from a pituitary adenoma, which can secrete excess hormones. Among the listed hormones, prolactin is the most commonly elevated in such tumors, particularly in prolactinomas, which are the most common functional pituitary adenomas.

**Why the Correct Answer is Right**
Prolactinomas are benign pituitary adenomas that secrete excessive prolactin, leading to hyperprolactinemia. This results in galactorrhea, infertility, and decreased sex hormone levels. Prolactin is produced by lactotrophs in the anterior pituitary and is regulated by dopamine via D2 receptors. A mass in the sella turcica disrupts normal hormone regulation, and prolactin is the most frequently overproduced hormone in such lesions.

**Why Each Wrong Option is Incorrect**
Option B: Thyroxine is produced by the thyroid gland, not the pituitary, and is not secreted by sella turcica masses.
Option C: "Extrogen" is not a recognized hormone; it is likely a typo or distractor.
Option D: ADH (antidiuretic hormone) is produced in the hypothalamus and released by the posterior pituitary; it is not secreted by sella turcica tumors and does not typically increase in pituitary masses.

**Clinical Pearl / High-Yield Fact**
Prolactinoma is the most common functional pituitary adenoma. Hyperprolactinemia causes galactorrhea and infertility, and treatment often involves dopamine agonists like cabergoline. Always consider prolactin when a sella turcica mass is suspected.

✓ Correct Answer: A. Prolactin