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': 'A 40 year old male patient complains of diminished vision during night and dryness of eyes. Patient gives history of recurrent bacterial infections. The plasma level of retinol binding protein in this patient will be: \nSelect and explain. \nA. Decreased, B. Increased, C. Unchanged, D. Fluctuating', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Night blindness (nyctalopia) is\xa0one\xa0of\xa0the\xa0earliest symptoms\xa0of\xa0vitamin\xa0A\xa0deficiency. Severe deficiency of\xa0vitamin\xa0A\xa0leads to xerophthalmia. The plasma level of retinol binding protein is decreased in vitamin A deficiency.\nSatyanarayana- Biochemistry, 3rd edition, pg-123', 'role': 'assistant'}]