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: Social & Preventive Medicine
[{'content': 'In a sample of 100 pregnant females, Mean haemoglobin level estimated was 10 gm% with a Standard deviation of 1 gm%. What is the Standard error? \nSelect and explain. \nA. 1 gm%, B. 0.1 gm%, C. 10 gm%, D. 100 gm%', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]