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

Which of the following classes is one valid superclass of 'D-galactono-1,5-lactone'?

A. ( Z)-6-benzylidene-3-hydroxymethyl-1,4-dimethyl-3-methylsulfanylpiperazine-2,5-dione
B. ( -)-1-hydroxybybetaochlamic acid
C. ((18)O)water
D. galactonolactone

Answer: galactonolactone