Route of administration of 25-hydroxyvitamin D3 (calcifediol) is:

Correct Answer: A

Rationale: The correct answer is A: Oral. Calcifediol is typically administered orally because it undergoes hepatic hydroxylation to form the active form of vitamin D, calcitriol. Subcutaneous (B) and intravenous (C) routes would bypass this necessary metabolic step. Intranasal (D) administration is not a common route for vitamin D supplementation. Therefore, oral administration ensures proper metabolism and bioavailability of calcifediol.

Correct Answer: C

Rationale: The correct answer is C: Destroying of bacterial cells. Bactericidal effect refers to the ability to kill bacteria. This is achieved by directly destroying the bacterial cells, leading to their death. Inhibition of bacterial cell division (A) and young bacterial cell growth (B) refer to bacteriostatic effects, which only stop bacterial growth but do not kill the bacteria. Formation of bacterial L-form (D) is a phenomenon where bacteria lose their cell wall and become resistant to antibiotics, but it does not directly relate to bactericidal action.

Correct Answer: B

Rationale: The correct answer is B: Local anesthetics – derivatives of paraaminobenzoic acid. Sulfonamides and local anesthetics both compete for the same metabolic pathway involving paraaminobenzoic acid, leading to decreased sulfonamide potency. Choices A, C, and D are incorrect because they do not interfere with the same metabolic pathway as sulfonamides, thus not affecting their potency.

Correct Answer: D

Rationale: The correct answer is D: Diloxanide. Diloxanide is a luminal amebicide, meaning it acts within the lumen of the intestines to target and eliminate amoebas residing there. This drug is specifically effective against amoebic cysts and is not absorbed systemically. Metronidazole (A) and Emetine (B) are tissue amebicides, which act systemically to target amoebas in tissues. Doxycycline (C) is an antibiotic commonly used for bacterial infections, not for treating amoebiasis. Therefore, Diloxanide (D) is the correct choice for a luminal amebicide drug.

Correct Answer: D

Rationale: The correct answer is D: All of the above. General contraindications for anticancer drugs include depression of bone marrow, which can lead to decreased production of blood cells; acute infections, as these drugs can further compromise the immune system; and severe hepatic and/or renal insufficiency, as these organs are responsible for drug metabolism and elimination. These contraindications are crucial to consider to prevent further harm to the patient. Choices A, B, and C individually are incorrect because they do not encompass all the general contraindications associated with anticancer drugs.