Which of the following fact(s) is/are true about sharpening spatial filters using digital differentiation?

• A. Sharpening spatial filter response is proportional to the discontinuity of the image at the point where the derivative operation is applied
• B. Sharpening spatial filters enhances edges and discontinuities like noise
• C. Sharpening spatial filters deemphasizes areas that have slowly varying gray-level values
• D. All of the mentioned