<span>Puberty begins when the pituitary gland increase the amount of hormones in one blood stream. Puberty is the process of physical change during which a child body's mature and become transformed into an adult body which is capable of reproduction. The onset of puberty is characterized by releasing of different types of hormones, especially reproductive hormones into the blood stream.</span><span />
B is the answer to the question
It enters the heart via the pulmonary veins
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