Concept:Cooked rice spoils quickly due to bacterial growth, and its earliest noticeable change is in texture and moisture.Explanation:Cooked rice contains moisture and starch, making it a good medium for bacteria.The first visible sign of spoilage is usually a slimy texture and watery or sticky appearance.This occurs before mould, colour change, or obvious maggots develop.Answer:B. sliminess and watery nature.