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: Medicine
All of the following statements regarding Rheumatoid ahritis are true, except? 
Select and explain. 
A. IgM antibody directed against Fc pa of IgG, B. Morning stiffness, C. Raised ESR, D. C - Reactive protein suggests a good prognosis
D: C - Reactive protein suggests a good prognosis
Answer: D: C - Reactive protein suggests a good prognosis 
Explanation: High ESR and CRP are associated with poor prognosis in rheumatoid ahritis. Rheumatoid factor (IgM antibody directed against Fc poion of IgG) and anti CCP antibody are present in 70-80% of cases. Anti CCP antibody are the most specific blood test for rheumatoid ahritis.