Task: Inferred Class Relation Reasoning (ontology: Sciences/Biology)

After reasoning, which of the following classes is one valid superclass of 'L-histidine:2-oxoglutarate aminotransferase activity'?

A. catalytic activity
B. neurotransmitter receptor transport to postsynaptic membrane
C. nephrocyte differentiation
D. regulation of cell diameter

Answer: catalytic activity