Final answer:
The finding of a low level of magnesium sulfate 4 mEq/L should be immediately reported to the provider, as it can indicate various conditions that require prompt medical attention.
Step-by-step explanation:
The correct answer is Option 1: Magnesium sulfate 4 mEq/L.
This finding should be immediately reported to the provider because low levels of magnesium can be indicative of several conditions including uremia, abnormal pregnancy, and hypercalcemia. These conditions require prompt medical attention and appropriate management.
Other options, such as peak serum gentamicin 6 mcg/mL, lithium carbonate 0.8 mEq/L, and digoxin 3.0 ng/mL, may also require monitoring and intervention, but they are not as critical as the low magnesium level.