<Li> Adding zinc to soil, called agronomic biofortification, which both increases crop yields and provides more dietary zinc . </Li> <Li> Adding zinc to food, called fortification . </Li> <Li> Adding zinc rich foods to diet . The foods with the highest concentration of zinc are proteins, especially animal meats, the highest being oysters . Per ounce, beef, pork, and lamb contain more zinc than fish . The dark meat of a chicken has more zinc than the light meat . Other good sources of zinc are nuts, whole grains, legumes, and yeast . Although whole grains and cereals are high in zinc, they also contain chelating phytates which bind zinc and reduce its bioavailability . </Li> <Li> Oral repletion via tablets (e.g. zinc gluconate) or liquid (e.g. zinc acetate). Oral zinc supplementation in healthy infants more than six months old has been shown to reduce the duration of any subsequent diarrheal episodes by about 11 hours . </Li>

Which of the following factors is known to decrease bioavailability of dietary zinc
find me the text answering this question