Lactation in stimulated by:

Explanation

The correct answer is Prolactin (LTH). Prolactin is the hormone primarily responsible for stimulating milk production in the mammary glands. It is secreted by the anterior pituitary gland and acts directly on the breast tissues to initiate and maintain lactation.Other hormones, such as human placental lactogen (hPL), play supportive roles during pregnancy by preparing the breast tissue for milk production, but they do not directly stimulate lactation. The placenta is crucial during pregnancy for hormone production but does not stimulate lactation. Instead, its removal after birth triggers hormonal changes that lead to prolactin release. Therefore, 'All of these' is incorrect as prolactin is the direct and primary stimulator of lactation.