Some bacteria are metabolically active in hot springs because

a. they are able to maintain a lower internal temperature.

b. high temperatures make catalysis unnecessary.

c. their enzymes have high optimal temperatures.

d. their enzymes are completely insensitive to temperature.

Their enzymes have high optimal temperatures.

Explanation:

Archaea is one of the domain among the three domains of life. Archaea bacteria are the bacteria that may exist in the extreme environmental condition.

Bacteria re also found at extreme temperatures conditions under the hotsprings. This is because these enzymes of this bacteria work at high optimal temperatures. Their enzymes are active at high temperature condition that makes them metabolically active.

Thus, the correct answer is option (c).