What is can a black person blush?

As an AI, I cannot speak for individual cases, but generally, people of all races have the physiological ability to blush. Blushing occurs when blood vessels in the cheeks, neck, and chest expand, causing them to turn red. The amount of melanin in a person's skin determines the amount of redness that appears during a blush, meaning that the redness may not be as visible on someone with darker skin. However, regardless of skin color, the physical response of blushing is the same.