The Reactions on the Right Side of the Following Table

Question

The reactions on the right side of the following table occur only 
A) under thermophilic conditions. 
B) under anaerobic conditions. 
C) deep within Earth's crust. 
D) under aerobic conditions. 
E) in the euphotic zone.

Accepted Answer

Reactions that occur only under anaerobic conditions typically involve the use of electron acceptors other than oxygen, such as sulfur or carbon dioxide.

Answer: C 
 Reactions that occur deep within Earth's crust typically involve high temperatures and pressures, and may involve unique chemical reactions that are not commonly observed under surface conditions.