The following regimen is preferred for nonsurgical termination of pregnancy in the first 7 weeks:

Correct Answer: D

Rationale: Step-by-step rationale for choice D being correct: 1. Oral mifepristone is a progesterone receptor antagonist, leading to detachment of the pregnancy. 2. Oral misoprostol, a prostaglandin, causes uterine contractions and expulsion of the products of conception. 3. This regimen is safe, effective, and widely used for early pregnancy termination. 4. Choice A, B, and C involve different medications and routes not typically used for nonsurgical termination of early pregnancy.

Correct Answer: A

Rationale: The correct answer is A: Rise in body temperature. Progesterone does not directly cause a rise in body temperature; this is primarily regulated by the hypothalamus. Progesterone's main actions include endometrial proliferation, proliferation of acini in the mammary gland, and suppression of cell-mediated immunity. Endometrial proliferation prepares the uterus for implantation, mammary gland proliferation prepares for lactation, and suppression of immunity prevents rejection of the fetus during pregnancy. Other choices are incorrect because they are well-documented actions of progesterone.

Correct Answer: D

Rationale: The correct answer is D: Improved lipid profile. Tamoxifen citrate therapy does not have a direct effect on improving lipid profile. A: Reduction in recurrence rate of breast cancer - Tamoxifen is used to reduce the risk of breast cancer recurrence. B: Improved bone mass - Tamoxifen can help maintain or improve bone density. C: Suppression of menopausal hot flushes - Tamoxifen can help reduce menopausal symptoms like hot flushes. In summary, choices A, B, and C are benefits of tamoxifen therapy, while choice D is not supported by evidence.

Correct Answer: D

Rationale: The correct answer is D (2-4 weeks) because rotating injection sites every 2-4 weeks helps prevent lipodystrophy and tissue damage. Insulin absorption may vary with frequent rotation, affecting glucose control. Choice A is too frequent and may lead to overuse of specific sites, increasing the risk of complications. Choice B is also too frequent and doesn't allow enough time for the tissue to recover. Choice C is too long, increasing the likelihood of uneven insulin absorption and potential complications. Rotation every 2-4 weeks strikes a balance between preventing damage and ensuring consistent insulin absorption.

Correct Answer: B

Rationale: The correct answer is B: Norepinephrine. The sympathetic postganglionic neurons release norepinephrine as the main neurotransmitter, which acts on target organs to elicit the fight-or-flight response. Norepinephrine is responsible for increasing heart rate, blood pressure, and dilating airways. Acetylcholine is released by preganglionic neurons in both sympathetic and parasympathetic systems, not postganglionic neurons in the sympathetic system. Option C is incorrect as acetylcholine is not typically released by postganglionic sympathetic neurons. Option D, arginine, is not a neurotransmitter commonly associated with the sympathetic nervous system.