How many percentage points did the risk drop after implementing controls?

• A. 60 percentage points
• B. 20 percentage points
• C. 40 percentage points
• D. 10 percentage points

Answer: (C)

This question tests how to measure a drop in risk using percentage points, which is simply the difference between the initial risk percentage and the post-control risk percentage. To get the number of percentage points dropped, subtract the post-control percentage from the pre-control percentage. For example, if risk started at 60% and ended at 20% after controls, the drop is 40 percentage points (60% − 20% = 40). This is an absolute change, not a percent change relative to the original value. So a 40-point drop is different from a 40% decrease in risk (which would be 40% of 60%, i.e., a 24-point decrease). The given answer reflects that absolute difference.