The images in the figure represent aqueous solutions of ionic compounds. Which could correspond to Na2S? 
Definitions:
Acromegaly
A condition characterized by overgrowth of the extremities of the skeleton, fingers, toes, jaws, and nose. It may be produced by excessive secretion of growth hormone by the anterior pituitary gland.
Gigantism
Abnormally tall growth caused when anterior pituitary secretes excessive amounts of human growth hormone during childhood
Pituitary Gland
A small gland located at the base of the brain responsible for releasing hormones that regulate various bodily functions, including growth, metabolism, and reproduction.
Hypothalamus
A region of the brain that regulates bodily functions such as temperature, hunger, and thirst, and is involved in controlling the pituitary gland.
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