The world health organization (who) estimates that about percent of all food is lost to food spoilage.

The World Health Organization estimates that about 20 percent of all food is lost to food spoilage. Some of the biological, chemical and physical changes that lead to spoilage are preventable by some preservation methods. Spoilage is characterized by a decline in eating quality, resulting in food that is less acceptable to the consumer in appearance, taste, texture or odor. The foods we eat are all derived from living matter making them subject to the natural process of decomposition. Food not only decomposes but it also lost or spoiled by being consumed by creatures other than humans which are rats, mice, flies and microorganisms. 

The answer is c : ) hope this answered your question!