16 year old male presents with extensive heterotropic ossification over the neck,back and shoulders and decreased chest movements.He gives history of progressive immobility since the age of 3 years.Which of the following statement about his affecting condition is not true?

• A. They have short hallux
• B. Increased expression of BMP4 gene is seen
• C. They have a near normal life expectancy
• D. They are predisposed to Pneumonia