Rickets is:

Correct Answer: A

Rationale: The correct answer is A because rickets is indeed a deficiency disease primarily affecting children due to lack of vitamin D, calcium, and sunlight exposure. Here's the rationale: 1. Rickets is characterized by defective bone growth, which aligns with the growth stage of children. 2. Rickets is caused by a lack of vitamin D or calcium, crucial for bone health. 3. Insufficient exposure to sunlight leads to decreased vitamin D synthesis. 4. Other choices are incorrect: - Choice B describes osteomalacia, a disease in adults, not rickets. - Choice C describes osteoporosis, a different condition in postmenopausal women. - Choice D is incorrect since rickets does not encompass all the conditions mentioned.

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: B

Rationale: Mineralocorticoids, such as aldosterone, act on the kidneys to increase sodium retention and potassium excretion. This process helps regulate blood pressure and electrolyte balance. Increased catabolism (choice A) is not a direct effect of mineralocorticoids. Increased gluconeogenesis (choice C) is a function of glucocorticoids, not mineralocorticoids. Deposition of fat on shoulders, face, and abdomen (choice D) is associated with Cushing's syndrome due to excess cortisol, not mineralocorticoids. Therefore, the correct answer is B as it aligns with the known physiological actions of mineralocorticoids.

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.