Correct Answer: D

Rationale: Sterilization is considered the most effective method of contraception because it permanently prevents pregnancy. Barrier methods, hormonal pills, and IUDs are highly effective as well, but they are reversible methods and may have a higher failure rate compared to sterilization.

Correct Answer: B

Rationale: The correct answer is B: Perineum. The perineum is the triangular space located between the vaginal and rectal canals. It is a region containing various muscles, nerves, and blood vessels that support the pelvic floor. Choice A, Pelvic floor, refers to the structure supporting the organs in the pelvic cavity, not the space between the vaginal and rectal canals. Choice C, Vestibule, is the space within the labia minora containing the openings of the urethra and vagina, not the area between the vaginal and rectal canals. Choice D, Perineal body, is a fibromuscular mass in the perineum area but not the space between the vaginal and rectal canals.

Correct Answer: B

Rationale: A human primary spermatocyte has 44 autosomes. Autosomes are chromosomes that are not involved in determining an individual's sex. In humans, there are a total of 46 chromosomes in a somatic cell, with 22 pairs of autosomes and one pair of sex chromosomes. Therefore, the correct answer is 44 autosomes, making choice B the correct answer. Choices A, C, and D are incorrect as they do not represent the accurate number of autosomes in a human primary spermatocyte.

Correct Answer: D

Rationale: The correct answer is D. During the menstrual phase of the menstrual cycle, the endometrium is shed up to the basal layer. This shedding occurs as a result of decreased levels of estrogen and progesterone, leading to the breakdown and subsequent shedding of the endometrial lining. Choice A, ovulation, is incorrect as ovulation is the release of an egg from the ovary, which occurs during the mid-cycle. Choice B, regenerative, is incorrect as it does not specifically refer to the phase where the shedding of the endometrium occurs. Choice C, secretory, is incorrect as it refers to the phase where the endometrium thickens in preparation for possible implantation of a fertilized egg, not shedding.

Correct Answer: B

Rationale: The correct answer is B because the Platypelloid pelvis indeed has an oval inlet. Gynaecoid pelvis, not mentioned in the choices, has a round inlet. Anthropoid pelvis has a long, narrow oval inlet, which makes choice C incorrect. Choice D is incorrect as the Android pelvis is actually heart-shaped with a narrowed inlet.