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: Orthopaedics
Osteoporosis is characterized most commonly by -a) Fracture vertebrab) Backache c) Bowing of legsd) Abdominal pain 
Select and explain. 
A. ab, B. a, C. ad, D. bc
A: ab
Answer: A: ab 
Explanation: Clinical features of osteoporosis 

Osteoporosis is an asymptomatic disorder unless complications (predominantly fractures) occur.
Most common symptom of osteoporosis is back pain secondary to vertebral compression fracture.
Dorso-lumbar spine is the most frequent site.
Other common sites of fracture are lower end radius (Colle's fracture) and fracture neck femur.