Incubation period of hepatitis B virus (HBV)?

Correct Answer: D

Rationale: Hepatitis B has a long incubation period, ranging from 30 to 180 days, depending on viral load and host factors.

Correct Answer: C

Rationale: Spermicides have the highest failure rate even with perfect use, making them less reliable.

Correct Answer: D

Rationale: Osler's nodes are painful, tender nodules found on fingers and toes, caused by immune complex deposition in infective endocarditis.

Correct Answer: B

Rationale: Renal tubular acidosis causes normal anion gap acidosis because it results from impaired renal acid excretion rather than accumulation of organic acids.

Correct Answer: A

Rationale: Dilutional hyponatremia occurs when there is excessive water retention relative to sodium. Conditions like heart failure cause fluid overload, leading to a dilution of serum sodium.