Step 1: Concept
Iron deficiency anemia is treated with oral or parenteral iron depending on the severity and patient tolerance.
Step 2: Meaning
Parenteral iron preparations must be designed to release iron slowly and safely into the bloodstream.
Step 3: Analysis
Ferrous gluconate (A) is a common oral iron supplement. Iron dextran (B), Iron sucrose (C), and Ferric carboxymaltose (D) are all injectable (parenteral) formulations.
Step 4: Conclusion
B, C, and D are parenteral preparations, while A is oral.
Final Answer: (C)