The correct option is A Prolactin
The placenta is the organ that provides the transfer of oxygen and carbon dioxide, as well as nutrients and wastes, between the mother and the fetus. It is also an endocrine gland that is only present during pregnancy. After delivery, the placenta is expelled from the mother's body as part of the afterbirth, and any hormones that were produced by the placenta fade from the mother's bloodstream.
Estrogen, Progesterone and Human chorionic gonadotropin are hormones secreted by the placenta.
Prolactin is an hormone secreted from anterior lobe of pituitary gland and it stimulates the growth of the mammary glands, lactation and maintenance of corpus luteum.