To identify the substance that is not a stimulant, the characteristics and effects of each option must be analyzed:
Based on this classification, Diamorphine is the substance that is not a stimulant.
| LIST I | LIST II | ||
|---|---|---|---|
| A | Vitamin A | II | Important for vision |
| B | Calcium | IV | Bone health |
| C | Iron | III | Oxygen transport in blood |
| D | Vitamin C | I | Absorption of iron |