From the given list, select the number of hormones which are not secreted by placenta:
FSH, LH, hCG, hPL, estrogen, progesterone, cortisol, prolactin, thyroxine, relaxin.

The placenta is an endocrine gland formed in the uterus of a pregnant woman. It provides oxygen and carbon dioxide, as well as nutrients between the mother and the foetus. Human chorionic gonadotropin (HCG), Progesterone, Estrogen and human placental lactogen are the hormones secreted by placenta. All the hormones play a very important role in the development of the foetus.
Relaxin is produced primarily by the corpus luteum, in both pregnant and non-pregnant females.
Cortisol is a steroid hormone adrenal glands, the endocrine glands on top of our kidneys, produce and release.
Prolactin is synthesized by lactotrophs in the anterior pituitary gland.

Hence, the correct answer is option “C”- Five.