Industrial melanism is an example of:
| 1. | Natural selection | 2. | Mutation |
| 3. | Racial difference | 4. | Predation |
Industrial melanism is an example of:
| 1. | Drug resistance |
| 2. | Darkening of the skin due to smoke from industries |
| 3. | Protective resemblance with the surroundings |
| 4. | Defensive adaptation of skin against ultraviolet radiations |