If the sperm cell fertilises the ovum, and implantation does not occur, then the corpus luteum degenerates and it turns into corpus albicans, stopping progesterone secretion. If fertilisation occurs and implantation also, the syncytiotrophoblast, the "root part" of the blastocyst (one of the early structures originated from the zygote), produces a hormone that is called <span>human chorionic gonadotropin (hCG). The hCG is what makes the corpus luteum keep secreting progesterone and maintain itself. The progesterone will then help keep the endometrium and, therefore, allow the development of the embryo to happen.</span>
Didn't mean to post this. sorry!
Andrew Jackson was a man who work very hard at his adulthood and became rich due to his hard efforts
he was inherited with wealth ,he was very humble person and was born poor and was a common man
so correct option is D hope it helps<span />
Answer: Timber industry, paper industry, furniture industry.
