Match the items in Column I with the items in Column II, and assign the correct code.

Column I

Column II

A. Cyanide process

1. Ultrapure Ge

B. Froth flotation process

2. Dressing of ZnS

C. Electrolytic reduction

3. Extraction of Al

D. Zone refining

4. Extraction of Au

5. Purification of Ni

 Codes

A B C D
1. 4 2 3 1
2. 2 3 1 5
3. 1 2 3 4
4. 3 4 5 1

Hint: Froth floatation process is used for dressing of ZnS.
A. Cyanide process is used for extraction of Au through the formation of anionic complex Au CN2-

B. Froth floatation process is used for dressing of ZnS.

C. Electrolytic reduction method is used for extraction of aluminium. Graphite electrode is used for this purpose.

D. Zone-refining is used for purification of Ge.