Final answer:
Smoldering pyrolysis is likely when an overheated household power cable maintains contact with wood in the stud space behind gypsum wall board.
Step-by-step explanation:
The correct answer is A) Smoldering pyrolysis. Pyrolysis is a high-temperature decomposition reaction that occurs without the presence of oxygen.
In the given scenario, when an overheated household power cable maintains contact with wood in the stud space behind gypsum wall board, pyrolysis can occur because the wood can undergo thermal decomposition due to high temperatures from the cable.
The thermal decomposition of the wood releases compounds, which can ignite and lead to smoldering pyrolysis.