Correct Answer: C

Rationale: Insomnia is a common symptom of menopause. During menopause, hormonal changes can lead to sleep disturbances, including difficulty falling asleep or staying asleep. Choice A, 'Bleeding per vagina,' is not a typical symptom of menopause but should prompt further evaluation. Choice B, 'Sleeping all the time,' is not a common symptom of menopause; in fact, insomnia, rather than excessive sleep, is more prevalent. Choice D, 'Increased concentration,' is not a symptom of menopause; cognitive changes like forgetfulness or difficulty concentrating may occur, but increased concentration is not a typical manifestation.

Correct Answer: D

Rationale: The correct answer is D, Spermicidal. The copper in Copper T exerts its action by affecting sperm viability and motility, thus preventing fertilization. Choices A, B, and C are incorrect because Copper T primarily works by preventing sperm from reaching and fertilizing the egg, rather than acting on blastocysts, bacteria, or bacteriocins.

Correct Answer: B

Rationale: The correct answer is B: Squamous epithelium. The vagina is lined with non-keratinized stratified squamous epithelium. This type of epithelium provides protection against abrasion and pathogens. Choice A, Ciliated epithelium, is incorrect as ciliated epithelium is found in areas like the fallopian tubes to help move the egg towards the uterus. Choice C, Columnar epithelium, is incorrect as columnar epithelium is typically found in areas like the intestines. Choice D, Transitional epithelium, is incorrect as this type of epithelium is found in areas like the urinary bladder.

Correct Answer: C

Rationale: The correct answer is C, 'Zona pellucida.' The ovum receives the sperm at the zona pellucida, which is the glycoprotein layer surrounding the plasma membrane of the oocyte. This layer plays a crucial role in preventing polyspermy. Choices A and B, 'Animal pole' and 'Vegetal pole,' are incorrect as they refer to different regions of the egg and are not where the sperm fertilizes the ovum. Choice D, 'None of the above,' is incorrect as the sperm indeed interacts with the zona pellucida during fertilization.

Correct Answer: A

Rationale: During the menstrual cycle, luteinizing hormone maintains the corpus luteum. The correct answer is A. Luteinizing hormone stimulates the corpus luteum to produce progesterone. Choice B, Follicle-stimulating hormone, is involved in stimulating the growth of follicles in the ovaries. Choice C, Progesterone, is produced by the corpus luteum and plays a role in preparing the endometrium for implantation. Choice D, Relaxin, is involved in processes such as softening the cervix and ligaments during pregnancy, but it is not responsible for maintaining the corpus luteum.