Genetics, Medical problems, eating habits etc
The answer is 'instinct'. This is innate complex behavior exhibited by an organism that is not learned. Some common examples are dogs shaking themselves dry when wet, honeybee communication via intricate dances, animal courtship behavior during mating season and the building of nests by birds.
Answer:
A - Hypothalamus and Antidiuretic Hormones
Explanation:
Whenever their is a sudden change in the fluid level in the bodyb, either the blood, sugar, etc., the osmoreceptors, a special group of cells within the hypothalamus part of the brain, will detect this.
Thereafter, a signal is sent to the posterior pituitary gland to release the antidiuretic hormones (ADH), whose job is to maintain the fluid level by causing an increase in water reabsorption into the body through the expansion of the epithelial cells of the kidney.