The nurse should prioritize administering intravenous fluids due to the infant's severe diarrhea and signs of dehydration, such as a sunken fontanelle. IV fluids provide rapid rehydration and appropriate monitoring for the child. Alternatives like oral rehydration solutions or withholding fluids are not appropriate given the severity of the situation.
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The nurse should prioritize administering intravenous fluids due to the infant's severe diarrhea and signs of dehydration, such as a sunken fontanelle. Oral rehydration should only be considered if the infant can tolerate fluids. IV fluids provide rapid rehydration and safety monitoring for the child. ;