Secretion from which of the following structures is preparing inner wall of uterus for implantation?
a)	Ovary	b)	Pituitary gland	c)	Corpus luteum	d)	Ovarian follicle

(c)

Corpus luteum acts as an endocrine gland. It is formed from the remaining structure of mature Graafian follicle which rupture at the time of ovulation and release ovum. Corona radiata and cumulus rophorus. It produces progesterone hormone during the second half of the menstrual cycle. It prepares the lining of uterus for implantation of fertilized egg.