Task: Class Definition Understanding (ontology: Sciences/Biology)

Which of the following definitions best describes 'biliverdin reductase [NAD(P)+] activity'?

A. Catalysis of the reaction: bilirubin IXalpha + NAD(P)+ = biliverdin IXalpha + NAD(P)H + H+.
B. Catalysis of the reaction: a flavan-3-ol + 2 NAD(P)+ = an anthocyanidin + 2 NAD(P)H + H+.
C. Catalysis of the reaction: 3-(cis-5,6-dihydroxycyclohexa-1,3-dien-1-yl)propanoate + NAD+ = 3-(2,3-dihydroxyphenyl)propanoate + H+ + NADH. Also converts (2E)-3-(cis-5,6-dihydroxycyclohexa-1,3-dien-1-yl)prop-2-enoate to (2E)-3-(2,3-dihydroxyphenyl)prop-2-enoate.
D. Catalysis of the reaction: (S)-dihydroorotate + NAD+ = H+ + NADH + orotate.

Answer: Catalysis of the reaction: bilirubin IXalpha + NAD(P)+ = biliverdin IXalpha + NAD(P)H + H+.