This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology and Rheumatology, Subject name: Medicine
Caplan's syndrome is? 
Select and explain. 
A. Pneumoconiosis with lymphadenopathy, B. Pneumoconiosis with CCF, C. Pneumoconiosis with HIV, D. Pneumoconiosis with rheumatoid arthritis
D: Pneumoconiosis with rheumatoid arthritis
Answer: D: Pneumoconiosis with rheumatoid arthritis 
Explanation: ANSWER: (D) Pneumoconiosis with rheumatoid arthritisREF: Harrison's 17th ed chapter 314'Caplan's syndrome first described in coal miners but subsequently found in patients with silicosis, includes seropositive rheumatoid arthritis with characteristic pneumoconiotic nodules''