Final answer:
After ferrous sulfate administration, a nurse should monitor for adverse effects such as nausea and vomiting, which are common side effects of the medication.
Step-by-step explanation:
A nurse monitoring a client after ferrous sulfate administration should be attentive to various possible adverse effects. Among those, nausea and vomiting are common reactions that can occur after taking ferrous sulfate. Other potential side effects that the nurse should be on the lookout for include dizziness, headache, fatigue, constipation, and in more severe cases, symptoms can escalate to jaundice, seizures, and even shock. Given the information provided, which mentions nausea, vomiting, diarrhea, and abdominal pain as adverse reactions, it's evident that gastrointestinal discomfort is a primary concern.
Therefore, out of the options provided, nausea and vomiting are known adverse effects of ferrous sulfate that the nurse should monitor for. It is important to note that each patient may react differently, and a comprehensive observation for any signs of adverse effects is crucial.