This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pathology
Valve usually not involved in rheumatic fever 
Select and explain. 
A. Mitral, B. Aoic, C. Pulmonary, D. Tricuspid
C: Pulmonary
Answer: C: Pulmonary 
Explanation: The mitral valve alone is involved in 70% of cases, with combined mitral and aoic disease in another 25%; the tricuspid valve usually is less frequently (and less severely) involved; and the pulmonic valve almost always escapes injury. (Robbins basic pathology,9th edition,pg no.391)