Organisms that live in physically harsh habitats are called extremophiles, and each type takes its name from the specific stress it has adapted to. The question is asking which name matches a high-salt habitat.
- Halophiles: The prefix "halo" refers to salt, so this name directly points to organisms built to survive and grow in high-salt water, such as salt lakes, salt pans and brine pools. They keep their cells from losing water to the salty surroundings using special internal solutes and pumps.
- Thermophiles: The prefix "thermo" points to heat, so these organisms are adapted to hot springs and deep sea vents, not salinity.
- Acidophiles: These grow in low pH surroundings, such as acidic mine drainage or acidic hot springs, which is a chemical stress unrelated to salt content.
- Psychrophiles: The prefix "psychro" means cold, describing organisms of polar ice and deep cold ocean water, again a different stress from salinity.
Since the question is specifically about a salty habitat, only the name built from "halo" (salt) fits. The other three names are built from prefixes for heat, acidity, and cold, none of which describe salt tolerance.
Let's summarize:
- Each extremophile name encodes the stress it survives: halo (salt), thermo (heat), acido (acid), psychro (cold).
- Only halophiles are defined by tolerance to high salt concentration.
So microbes that grow in salty areas are correctly called halophiles.