Final answer:
A nurse should monitor for respiratory depression following administration of magnesium sulfate 1 G IV bolus, as it can lead to decreased respiratory function.
Step-by-step explanation:
When a nurse is assessing a client following the administration of a magnesium sulfate 1 G IV bolus, they should monitor for possible adverse effects, one of which is respiratory depression. Magnesium sulfate is a central nervous system depressant and an increase in magnesium levels can lead to decreased respiratory function. Therefore, among the options provided, respiratory depression is the correct answer. It is crucial to closely monitor the client for this adverse effect to prevent any serious complications.