Explanation

(c)
Benedict’s solution contains ${CuSO}_{4},\ {Na}_{2}{CO}_{3}$ and sodium citrate. This permits formation of a complex, which lowers the concentration of Cu (II) ions to such an extent that it doesn’t permit the precipitation of insoluble $Cu(OH)_{2}.$ Benedict’s solution is more stable than Fehling’s solution is not affected by substance like uric acid present in urine. Hence, it is preferred to detect the presence of glucose in urine.