Final answer:
The best possible means to conduct a forcible entry in this situation would be to utilize a pry bar or some similar tool to wedge open the door at the jamb.
Step-by-step explanation:
The best possible means to conduct a forcible entry in this situation would be to utilize a pry bar or some similar tool to wedge open the door at the jamb (option B). This method is effective for gaining entry without causing excessive damage or risk of explosion, as would be the case with options A and D. Using a fireman's axe to create a hole in the door (option C) may also be a viable option, but it is generally safer and more efficient to use a pry bar for forcible entry.