A hormone is a secreted molecule that is carried in the bloodstream to where it acts on target cells that bear specific receptors for that hormone.

The hypothalamus is the part of the brain that produces hormones that control the pituitary gland.
The pituitary gland then releases hormones that target other endocrine glands, such as the thyroid, adrenal, and gonads.
Therefore, the hypothalamus is the source of releasing hormones for target cells in the anterior pituitary gland.
Choice A is wrong because the anterior pituitary gland does not produce releasing hormones, but responds to them by secreting other hormones.
Choice C is wrong because the thyroid gland does not produce releasing hormones, but responds to them by secreting thyroid hormones.
Choice D is wrong because the posterior pituitary gland does not produce releasing hormones, but stores and releases hormones made by the hypothalamus, such as oxytocin and antidiuretic hormone.

Circulation is the movement or flow of something, especially blood or air, through a circuit or a specific course.
Circulation supplies oxygen and nutrients to and removes wastes from tissues. This is essential for the survival and functioning of cells and organs.
Choice A is wrong because circulation does not inflate the lungs.
The lungs are inflated by the pressure difference between the air inside and outside the chest cavity.
Choice C is wrong because circulation does not deliver waste to tissues.
Circulation removes wastes from tissues and delivers them to the excretory organs such as the kidneys and the lungs.
Choice D is wrong because circulation does not deliver carbon dioxide to tissues and removes excess oxygen.
Circulation does the opposite: it delivers oxygen to tissues and removes carbon dioxide.
Carbon dioxide is a waste product of cellular respiration that needs to be eliminated from the body.