Match the following using the code given below.
| A. Tungsten | 1. Development of human civilization |
| B. Titanium | 2. Light bulb filament |
| C. Molybdenum | 3. Artificial ***** |
| D. Copper | 4. Boiler plant |
| | A | B | C | D |
| (a) | 2 | 3 | 4 | 1 |
| (b) | 3 | 2 | 1 | 4 |
| (c) | 4 | 1 | 3 | 2 |
| (d) | 1 | 4 | 2 | 3 |