Match List - I with List - II and select the correct answer using the codes given below:
| List - I | List - II | ||
| A. | Nitriding | 1. | Improves the hardness of whole mass |
| B. | Annealing | 2. | Refined grain structure |
| C. | Martempering | 3. | Improves surface hardness |
| D. | Normalizing | 4. | Improves ductility |
1
(A)-(3), (B)-(2), (C)-(4), (D)-(1)
2
(A)-(3), (B)-(4), (C)-(1), (D)-(2)
3
(A)-(1), (B)-(2), (C)-(3), (D)-(4)
4
(A)-(1), (B)-(3), (C)-(4), (D)-(2)