Which statement best describes CEP?

• A. Circular Error Probable is the radius of a circle with the center at the DPI
• B. Circular Error Probable is the radius of a circle with the center at the desired point of impact (DPI)
• C. Circular Error Probable is the indicator of the delivery accuracy of a weapon
• D. Circular Error Probable is the standard deviation of impact distances

Answer: (C)

Circular Error Probable is a statistical measure of how accurately a weapon delivers its effects. It expresses the dispersion of impact points by a single distance: the radius of a circle, centered on the mean impact point, within which 50 percent of the rounds are expected to land. That makes CEP a practical indicator of delivery accuracy, because it directly ties the spread of hits to a probability—how tightly the rounds cluster around the intended point.

The other descriptions don’t fit as well. CEP is not simply a fixed circle centered on the desired point of impact in every case, since the center is the mean impact location, which may differ from the intended aim point if there’s bias. And CEP is not the standard deviation of impact distances; it describes a probability-based radius for 50% of hits, not a dispersion measure like standard deviation.