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
Severe Laxity of joints - a) Marfan's syndrome   b) Ehler Danlos  c) RA  d) Osteogenesis imperfecta  e) OA 
Select and explain. 
A. ab, B. abc, C. ade, D. ae
A: ab
Answer: A: ab 
Explanation: None