I think it is C, though not sure. Hope this helps you.
The gases being released from the ground
Answer:
The carbon in the air will lessen over time. This is because it is being trapped in the walls of the biodome. This will affect living things negatively as the carbon cycle is a necessary part of nature and throwing off the balance of carbon in the carbon cycle will throw off the balance of the entire ecosystem within the biodome.
It would be the first option. Adenine and thymine.
