(d) 5 A
Current drawn = P/V = 1000/220 = 4.54 A. Since fuse rating must be just above the operating current, a 5 A fuse must be used.
Source: Chapter 11, Section 11.7.1
The textbook explicitly gives this identical example (electric iron, 1 kW at 220 V → 4.54 A → use 5 A fuse). A fuse must be rated above the normal operating current but at the nearest standard value to give proper protection. Standard domestic fuse ratings are 1 A, 2 A, 3 A, 5 A, 10 A — so 5 A is correct.