Which of the following hormones is secreted by the pituitary gland?

The hormone secreted by the pituitary gland is oxytocin. This hormone plays a significant role in various physiological processes, including the regulation of social bonding, sexual reproduction, and childbirth. It is produced in the hypothalamus but is stored and released by the posterior pituitary gland.

Oxytocin is particularly known for its role in stimulating uterine contractions during labor and facilitating lactation by promoting the contraction of smooth muscle cells surrounding the mammary glands. Its effects on social behaviors and emotional bonding are also well-documented, making it a critical hormone in both maternal and social interactions.

Cortisol is produced by the adrenal glands and is involved in the stress response, while insulin is secreted by the pancreas and is crucial for regulating blood glucose levels. Adrenaline (or epinephrine) is also released by the adrenal glands and is associated with the body's fight-or-flight response. Therefore, these hormones, while important in their roles, are not secreted by the pituitary gland.