Question

1. what group of archaea is both thermophilic and acidophilic?

halophiles
pyrogens
methanogens
thermoacidophiles

Explanation:

• Halophiles: These organisms thrive in high - salt environments. The term "halo" refers to salt, so they are not related to heat (thermo) or acid (acid) preferences.
• Pyrogens: Pyrogens are substances that cause fever in animals. This is not related to the environmental preferences (thermophilic and acidophilic) of Archaea.
• Methanogens: Methanogens are Archaea that produce methane. Their metabolic characteristic (methane production) is not related to being thermophilic (heat - loving) and acidophilic (acid - loving).
• Thermoacidophiles: The name "thermoacidophiles" is a combination of "thermo" (heat) and "acid" (acid). These Archaea are adapted to live in hot and acidic environments, which matches the description of being both thermophilic and acidophilic.

Answer:

thermoacidophiles