The presence of which hormone confirms pregnancy?

Correct Answer: D

Rationale: The correct answer is D: hCG. Human Chorionic Gonadotropin (hCG) is produced by the placenta after implantation, confirming pregnancy. Estrogen (A) and Progesterone (C) are important hormones in pregnancy but do not specifically confirm it. FSH (B) is Follicle-Stimulating Hormone, which is not directly related to pregnancy confirmation. hCG is the most reliable indicator of pregnancy as its levels rise significantly in early pregnancy, making it the correct choice.

Correct Answer: C

Rationale: The corpus luteum is formed from the ruptured follicle after ovulation. It secretes progesterone to prepare the uterine lining for implantation and maintain pregnancy. This is essential for supporting early pregnancy until the placenta takes over progesterone production. Choices A and D are incorrect as the corpus luteum primarily produces progesterone, not estrogen or stimulates follicle development. Choice B is incorrect as the corpus luteum does not prevent ovulation but rather supports pregnancy post-ovulation.

Correct Answer: B

Rationale: Testosterone is the correct answer because it is the primary male sex hormone responsible for the development and maintenance of the male reproductive system, including the development of male sex organs like the testes and penis. Estrogen (A) is the primary female sex hormone, not responsible for male reproductive system development. Progesterone (C) is involved in the female reproductive system and pregnancy, not in male development. FSH (D) is a follicle-stimulating hormone that plays a role in both male and female reproductive systems but is not responsible for the development of the male reproductive system specifically.

Correct Answer: B

Rationale: The primary purpose of the placenta during pregnancy is to provide oxygen and nutrients to the fetus. The placenta acts as a bridge between the mother and the fetus, allowing for the exchange of oxygen, nutrients, and waste products. It filters oxygen and nutrients from the mother's blood to the fetus and removes waste products from the fetal blood to the mother's circulation. This process ensures the proper growth and development of the fetus. Choice A is incorrect because the placenta does not excrete waste products, it filters them. Choice C is incorrect as the placenta does not regulate the fetus's temperature. Choice D is incorrect because hCG (human chorionic gonadotropin) is a hormone produced by the embryo, not the placenta.

Correct Answer: C

Rationale: The correct answer is C because the main function of the female reproductive system is to provide a site for fertilization and support embryo development. This includes the production of eggs, the site for fertilization in the fallopian tubes, and the nurturing of the embryo in the uterus. Choices A and D are partially correct as the female reproductive system also produces hormones and regulates the menstrual cycle, but these are not the main functions. Choice B is incorrect as supporting fetal development occurs after fertilization and embryo development, which are the primary functions of the female reproductive system.