Final answer:
The bloat stage (B) is the correct answer where bacteria activities lead to the buildup of carbon dioxide gas in a decomposing corpse. This stage is characterized by the bloating of the corpse due to gaseous expansion from microbial decomposition.
Step-by-step explanation:
The correct answer to the decompositional stage where bacteria arrive and carbon dioxide gas builds up in the corpse is B) Bloat stage.
Bacteria, known as decomposers, are vital participants in the carbon cycle. They break down dead organic matter, releasing nutrients and carbon dioxide back into the environment. The buildup of gases, primarily carbon dioxide, produced by microbial activity creates a bloated appearance in a decomposing corpse during the bloat stage. Bogs, with their low oxygen content and acidic environment, can slow down decomposition, preserving bodies for extended periods. However, in normal conditions where bacteria can thrive, they use the organic substrates of the corpse to gain energy, carbon, and nutrients they need, leading to the typical stages of decomposition, with the bloat stage being one of the most visually noticeable due to the gaseous expansion of the body.