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

Which of the following classes is one valid superclass of 'cardiac muscle cell action potential'?

A. 3-keto-sphinganine metabolic process
B. 5,6,7,8-tetrahydromethanopterin biosynthetic process
C. (1->3)-beta-D-glucan catabolic process
D. action potential

Answer: action potential