Task: Question Answering
Input (English): Question: To estimate the plasma clearance of a drug (CLIR) that presents a linear kinetic behavior and is excreted significantly in the urine, in a patient with renal failure (RI), it is necessary to know: 
 Options:  <1> Clearance of creatinine in the uremic patient (CLcrIR) and in individuals with normal renal function (CLcrFRN). <2> The renal clearance of the drug in patients with normal renal function (CLrFRN), CLcrIR and CLcrFRN. <3> The fraction of drug excreted in unaltered form in the urine (fr), the dose administered (D), CLrFRN, CLcrIR and CLcrFRN. <4> fr, CLcrIR and CLcrFRN and the plasma clearance of the drug in patients with normal renal function <5> fr, CLrFRN, CLcrIR, CLcrFRN and D.
Output (English): 4