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The correct choice is based on understanding how nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen can affect renal hemodynamics, especially in patients with a history of congestive heart failure (CHF). In this context, ibuprofen can inhibit the synthesis of prostaglandins, which are crucial for maintaining afferent arteriolar dilation.

In patients with CHF, there is often a state of reduced renal perfusion due to decreased cardiac output, and the kidneys rely on prostaglandins to help dilate the afferent arterioles to maintain adequate glomerular filtration rate (GFR). When ibuprofen is used, the inhibition of prostaglandin production leads to reduced vasodilation of the afferent arterioles, resulting in decreased renal blood flow and consequently causing transient renal impairment. This effect is particularly pronounced in vulnerable populations, such as those with existing heart failure or compromised renal function.

Therefore, the mechanism described explains how the use of ibuprofen can induce transient renal failure by compromising the normal regulatory mechanisms of renal blood flow, ultimately leading to impaired kidney function due to decreased perfusion.