This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
The first step in liver’s metabolism of fructose is ? 
Select and explain. 
A. Isomerization of glucose, B. Phosphorylation to fructose 1, 6 bisphosphate by ATP, C. Phosphorylation to fructose 6 phosphate by ATP, D. Phosphorylation to fructose 1 phosphate by ATP
D: Phosphorylation to fructose 1 phosphate by ATP
Answer: D: Phosphorylation to fructose 1 phosphate by ATP 
Explanation: Fructose metabolism