Choose the drug affecting the biliary system and relaxing Oddy sphincter:

Correct Answer: C

Rationale: The correct answer is C: No-spa. No-spa is the drug that affects the biliary system and relaxes the Oddi sphincter. The Oddi sphincter is a muscular valve that controls the flow of bile and pancreatic juice into the duodenum. No-spa, also known as Drotaverine, is a smooth muscle relaxant that works by inhibiting phosphodiesterase enzyme, leading to relaxation of smooth muscles including the Oddi sphincter. Choices A, B, and D are incorrect as they do not specifically target the biliary system or the Oddi sphincter. Cholosas is a liver protectant, Oxaphenamide is a carbonic anhydrase inhibitor, and Cholenzyme is a combination of digestive enzymes.

Correct Answer: D

Rationale: The correct answer is D, as calcium channel blockers have multiple effects on the cardiovascular system. They reduce peripheral vascular resistance by dilating blood vessels, decrease cardiac contractility and output by blocking calcium entry into cardiac muscle cells, and relieve coronary artery spasm by dilating coronary arteries. Therefore, all of the choices (A, B, and C) are correct effects of calcium channel blockers. The other choices are incorrect because they do not encompass all the effects of calcium channel blockers.

Correct Answer: B

Rationale: The correct answer is B because at low doses, dopamine primarily acts on dopamine receptors, leading to vasodilation of renal and mesenteric vessels. This is known as the renal dose of dopamine. Choices A and C are incorrect because low doses of dopamine do not significantly impact alpha-adrenoreceptors for peripheral vasoconstriction or beta-1 adrenoreceptors for enhancing cardiac output. Choice D is incorrect as dopamine at low doses does not affect all the mentioned receptors simultaneously.

Correct Answer: B

Rationale: Step-by-step rationale: 1. Diatrizoate sodium is a contrast agent, not an antithyroid drug. 2. Propylthiouracil, Methimazole, and Potassium perchlorate are antithyroid drugs. 3. Propylthiouracil and Methimazole inhibit thyroid hormone synthesis. 4. Potassium perchlorate blocks iodine uptake by the thyroid gland, reducing hormone production. 5. Thus, Diatrizoate sodium is the correct answer as it is not an antithyroid drug.

Correct Answer: D

Rationale: The correct answer is D because mifepristone (RU-486) acts in multiple ways to terminate pregnancy. It inhibits ovulation by blocking progesterone receptors, suppresses midcycle gonadotropin release, inhibits progesterone action on the uterus during the luteal phase, induces prostaglandin release from the endometrium, facilitates luteolysis, induces menstruation, increases uterine motility, softens the cervix, and causes detachment of the embryo. Therefore, all the actions described in options A, B, and C are correct, making option D the correct choice. Options A, B, and C are incorrect because they each only describe a single aspect of mifepristone's mechanism of action, whereas option D encompasses all the actions of mifepristone.