Final answer:
To extract salt from a deposit far underground, subsurface mining (c) is the best approach because it allows for the extraction of minerals deep beneath the earth's surface without significant surface disturbance and is environmentally more preferable than mountaintop removal mining.
Step-by-step explanation:
If you are a mine manager and you want to extract salt from a deposit far underground, the most suitable mining approach would be c) Subsurface mining. This method involves extracting minerals from beneath the earth's surface. Since the salt deposit in question is located far underground, surface mining methods like open-pit mining, which is used for deposits near the surface, would not be appropriate. Furthermore, placer mining is typically used for materials found in all-uvial deposits such as gold rather than for salt. Mountain-top removal mining is also not suitable as this method is mainly used for extracting coal by removing the summit of mountains, and it has significant environmental and ecological impacts.
Subsurface mining is often used for mining salt, especially when it is located deep below the surface. This method minimizes surface disturbance and can be more cost-effective when dealing with deep deposits. Moreover, considering the environmental concerns and required expertise, subsurface mining is more preferable since it is less damaging to the environment as compared to mountaintop removal and is better suited for extracting minerals found deep within the earth.