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: Biochemistry
[{'content': 'Monosaccharide with no Asymmetric Carbon- atom- \nSelect and explain. \nA. a) Ribulose, B. b) Erythrulose, C. c) Xylulose, D. d) Dihydroxyacetone', 'role': 'user'}, {'content': 'Answer: D \nExplanation: - CH2OH | C=O | CH2OH', 'role': 'assistant'}]