This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood, Subject name: Medicine
[{'content': 'Bence jones proteins are: \nSelect and explain. \nA. Heavy chain Ig G, B. Present in bone marrow, C. Seen in lymphoma, D. Light chain IgG', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans: dRef: CMDT 2004, p. 1731 see index, Harrison, 16thed, p. 659', 'role': 'assistant'}]