Which of the following is a characteristic of high glycemic index foods?

High glycemic index (GI) foods are characterized by their ability to cause a rapid increase in blood sugar levels after consumption. This occurs because such foods are often quickly digested and absorbed into the bloodstream, leading to a swift spike in glucose levels. Foods that fall into this category generally include those that are high in sugars and refined carbohydrates, such as white bread, sugary cereals, and many snack foods.

In contrast, options such as slow digestion, low calorie content, and high fiber content do not align with the characteristics of high GI foods. Slow-digesting foods are generally associated with a low GI, providing a more gradual release of glucose into the bloodstream. Low calorie and high fiber foods also often have a lower glycemic impact, making them beneficial for blood sugar control. Thus, the defining feature of high glycemic index foods is their ability to significantly and quickly elevate blood sugar levels.