What can be inferred about some fires based on the bulletin?

The assertion that some fires are extinguished without help from the Fire Department is substantiated by the bulletin. This indicates that in certain situations, individuals or small groups are capable of addressing and managing fires effectively on their own before professional assistance arrives. This can occur in cases where the fire is minor or can be quickly controlled, suggesting the ability of trained personnel or emergency response plans in place to handle such incidents without necessitating immediate Fire Department intervention.

The other options imply absolute scenarios that do not align with the information presented in the bulletin. For instance, stating that all fires require the Fire Department's assistance overlooks the possibility of these minor incidents being contained independently. Similarly, claiming that the Fire Department always arrives before fires are put out ignores instances where initial containment occurs before they can respond. Lastly, suggesting that no fires are ever contained by subway employees dismisses the reality that some employees are trained to handle certain emergencies, including initial fire response. Thus, option B accurately reflects a more nuanced understanding of fire management as discussed in the bulletin.