If osteoclast-driven resorption increases by 3.0% per year while osteoblast deposition remains 1.0% per year, calculate the percent decrease in bone density over 5 years (compound) and state which compartment will show the earliest and largest loss.

• A. Approximately a 2% total decrease over 5 years since net loss is only 2% and losses do not compound; neither compartment is especially vulnerable.
• B. About a 9.61% decrease over 5 years (final ≈90.39% of baseline); trabecular bone shows earliest/largest loss.
• C. About a 15% decrease over 5 years due to additive annual losses; cortical bone will be disproportionately affected because it comprises most skeletal mass.
• D. No significant decrease because deposition buffers increased resorption; both compartments remain stable with minor fluctuations.

Answer: (B)