This is a contrast-safety question built on the NSF risk classification of gadolinium agents. Linear chelates (Group I) are the riskiest, macrocyclic chelates (Group II) are essentially risk-free for NSF, and Group III carries insufficient evidence.
The teaching point about Group II agents is their freedom from significant NSF risk: they can be administered to patients with poor renal function and do not strictly require an eGFR check beforehand. The vignette therefore looks for the patient in whom renal function is the limiting concern.
The option describing GFR $<50$ mL/min is exactly that patient, and a Group II agent is safe for them. The "no RFT" choices address screening policy rather than safety in renal disease, while the normal-RFT patient could take any agent and so does not isolate the Group II advantage.
The best answer is the patient with low GFR.
\[\boxed{\text{GFR }<50\text{ — Group II GBCA is safe}}\]