What is the definition of the ‘Glycaemic Index (GI)’?

A. The daily energy requirement an average height person needs to maintain a healthy weight

B. The daily intake level of a nutrient needed to meet the needs of 97.5% of a population group

C. It was the guideline for daily nutrient intake to meet the needs of most people prior to 1997

D. It is a direct measure of the rate at which blood glucose rises after consuming a carbohydrate food