This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolic and endocrine disorders, Subject name: Orthopaedics
Z score measures the bone mineral density compred to - 
Select and explain. 
A. Age, Race and sex matched individuals, B. Race and sex matched individuals, C. Sex matched individuals, D. None of the above
A: Age, Race and sex matched individuals
Answer: A: Age, Race and sex matched individuals 
Explanation: A Z-score compares your bone density to the average values for a person of your same age and gender. A low Z-score (below -2.0) is a warning sign that you have lessbone mass (and/or may be losingbone more rapidly) than expected for someone your age. Ref essential ohopaedic maheshwari and mhaskar 9TH ED