Which investigation is not recommended for assessment of bothersome lower urinary tract symptoms?

Correct Answer: D

Rationale: Ultrasound abdomen/pelvis isn't recommended for initial LUTS assessment optional for complications (e.g., hydronephrosis), not routine. IPSS quantifies symptoms essential. DRE checks prostate size standard. Uroflow measures obstruction key. USS's secondary role distinguishes it, critical for guideline-based evaluation, unlike primary tools.

Correct Answer: B

Rationale: Potassium is reabsorbed in exchange for sodium in the distal tubule (Na+/K+ pump), not chloride (co-transported), calcium, or magnesium (different mechanisms). This distinguishes ion exchange, key for electrolyte balance, contrasting with passive processes.

Correct Answer: D

Rationale: Microvilli maximize surface area in the PCT for reabsorption, not loop or DCT (fewer). This specifies absorptive structure, key for efficiency, contrasting with minimal presence elsewhere.

Correct Answer: B

Rationale: Minor calyces collect urine from papillae first, before pelvis, ureter, or urethra. This identifies initial collection, key for urine flow, contrasting with downstream structures.

Correct Answer: A

Rationale: Creatine isn't secreted (converted to creatinine), unlike creatinine, H+ (acid-base), and penicillin (drugs). This distinguishes secretion profile, key for excretion, contrasting with metabolized compounds.