A section in the kidney shows one of the followings:

Correct Answer: B

Rationale: Kidney cortex has glomeruli, medulla has pyramids; columns of Bertini (cortical extensions) lie between medullary pyramids not pyramids in cortex or glomeruli in medulla. This distinguishes renal architecture, vital for sectional anatomy, contrasting with misplacements.

Correct Answer: C

Rationale: Proximal tubules reabsorb nearly all filtered glucose (100% normally), not secreted, partial (60-70%), or passively for amino acids (active). This distinguishes PCT's reabsorptive capacity, vital for nutrient retention, contrasting with secretion or partial views.

Correct Answer: D

Rationale: Renin rises with hypovolemia, DCT hyponatremia (macula densa), and sympathetic input not PCT (no sensing role). This distinguishes renin triggers, vital for blood pressure regulation, contrasting with tubular mislocation.

Correct Answer: B

Rationale: Struvite (magnesium ammonium phosphate) crystals appear rectangular (coffin-lid shape) under microscopy classic infection stone marker (e.g., urease bacteria). Needle-shaped fits urate or cystine wrong chemistry. Amorphous lacks distinct form, unlike struvite's structure too vague. Hourglass isn't typical confuses with other forms. Rectangular morphology distinguishes struvite, key to identifying infection-driven stones, unlike sharp, shapeless, or misattributed shapes.

Correct Answer: D

Rationale: Optimal surgery for GUTB is 4-6 weeks post-therapy, not 1 week allows inflammation reduction, incorrect timing. GUTB is second to pulmonary in developing areas true prevalence. Kidney involvement is ~80% primary site. Urine AFB culture is gold standard specific diagnosis. Delayed surgery distinguishes correct management, key to balancing medical and surgical needs, unlike true epidemiology or diagnostics.