Final answer:
The nurse should assist the patient to ambulate to encourage gastrointestinal motility and help relieve the sharp, cramping gas pains.
Step-by-step explanation:
The most appropriate action by the nurse when a patient complains of sharp, cramping gas pains four hours after being placed on a clear liquid diet post removal of a nasogastric (NG) tube would be c. Assist the patient to ambulate. This encourages gastrointestinal (GI) motility, which can help to alleviate gas pains. None of the other options directly address this issue: Reinserting the NG tube (option a) is usually not necessary unless there are signs of significant nausea, vomiting or abdominal distention, giving the PRN IV opioid (option b) may mask symptoms rather than treat the cause of pain, and placing the patient on NPO status (option d) will not relieve the gas pains and may further delay GI recovery.