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

Which of the following classes is one valid superclass of 'L-proline biosynthetic process'?

A. (1->3)-beta-D-glucan binding
B. (R)-mevalonic acid biosynthetic process
C. proline biosynthetic process
D. 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)ethane catabolic process

Answer: proline biosynthetic process