Final answer:
Iron is an essential nutrient for infants and should not be omitted from their diet. Low-fat milk, hot dogs, and corn syrup are not suitable for infants and should be avoided.
Step-by-step explanation:
The question that needs to be answered is which of the following should not be omitted from an infant's diet. The options given indicate that only one of these is suitable for an infant. According to recommendations, iron is a necessary nutrient for infants and should be included in their diet as it supports critical functions and development. On the other hand, items such as low-fat milk contain proteins that are hard for infants to digest, and therefore, cow's milk is not advisable for infants. Similarly, foods like hot dogs are a choking hazard and contain ingredients that are not suitable for an infant, and corn syrup is an added sugar that should be avoided in an infant's diet. Therefore, the only item that should not be omitted from an infant's diet is iron.