Correct option is D
✅ (d) None of these: • Among the listed options, none is the first systemic fungicide. • The first true systemic fungicide used was Carboxin (also present in formulations like Vitavax), but it was not the first among the ones listed. • Dithane M-45 and Z-78 are contact fungicides, not systemic.
❌ (a), (b), (c): • Not the first systemic ones, although widely used.