Pre renal failure occurs in

Correct option is A

Pre-renal failure results from conditions that reduce renal perfusion without direct damage to the kidneys. Heart failure lowers cardiac output, leading to decreased blood flow to the kidneys and pre-renal acute kidney injury (AKI).
Explanation of each option: • (a) Heart failure – Correct. Decreased perfusion due to poor cardiac output causes reduced glomerular filtration, leading to pre-renal AKI. • (b) Nephrolithiasis – Causes post-renal failure due to obstruction of urine outflow, not decreased perfusion. • (c) Toxic nephropathy – This results in intrinsic renal failure, where kidney tissues are directly damaged by toxins or drugs. • (d) Glomerulonephritis – Also intrinsic renal failure due to inflammation of glomeruli, not reduced blood supply.