2.Etiology C. Disorders of nerve and muscle Poliomyelitis disorders of motor-nerve center D. Disorders of pulmonary vessels Hypersensitive granuloma embolism of pulmonary artery E. pulmonary arterial hypertension of unknown cause2.Etiology C. Disorders of nerve and muscle Poliomyelitis disorders of motor-nerve center D. Disorders of pulmonary vessels Hypersensitve granuloma → embolism of pulmonary artery E. pulmonary arterial hypertension of unknown cause