Consider the following statements: 1. Some microorganisms can grow in environments with temperature above the boiling point of water. 2. Some microorganisms can grow in environments with temperature below the freezing point of water. 3. Some microorganisms can grow in highly acidic environment with a pH below 3. How many of the above statements are correct?

1. A. Only one
2. B. Only two
3. C. All three
4. D. None

Answer: C

Explanation

1. Statement 1 is correct: Thermophilic and hyperthermophilic microorganisms, particularly archaea, can thrive in extremely hot environments. For example, Pyrolobus fumarii can grow at temperatures up to 113°C, well above the boiling point of water. 2. Statement 2 is correct: Psychrophilic or cryophilic microorganisms are extremophiles that can grow and reproduce in cold temperatures, including those below the freezing point of water (e.g., in polar regions or deep-sea environments). 3. Statement 3 is correct: Acidophilic microorganisms are adapted to highly acidic conditions. Extreme acidophiles can grow optimally at pH values below 3, found in environments like acid mine drainage or volcanic hot springs. Therefore, all three statements are correct.