Which Statement Concerning Bile Pigments Is TRUE

Which statement concerning bile pigments is TRUE?

A) heme oxygenase requires NAD and molecular oxygen for activity.
B) Inactivity of glucuronyl transferase may lead to accumulation of toxic levels of free bilirubin in the tissues.
C) Carbon dioxide and ferrous ions are released in the oxidation of heme.
D) The formation of bilirubin from biliverdin requires cytochrome P450.
E) Nearly all heme is eventually converted to urobilinogen, some of which normally is excreted in the urine.