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

Which of the following classes is one valid superclass of 'L-alanine import across plasma membrane'?

A. amino acid import across plasma membrane
B. ABC-type monosaccharide transporter activity
C. 6,7-dihydropteridine reductase activity
D. 2'-deoxyribonucleotide metabolic process

Answer: amino acid import across plasma membrane