What is one indicator that could suggest where a victim might be located in a smoke-filled environment?

In a smoke-filled environment, an effective indicator for locating a victim is the sound of movement. This option emphasizes the importance of auditory cues in a situation where visibility is severely compromised due to smoke. Noise can potentially guide rescuers toward a victim's location, as sounds like cries for help or movements can travel through smoke more clearly than visual cues.

While strong odors and heat signatures can provide clues, they are not as reliable as sound, especially when smoke alters perceptions. It's also important to note that floor HVAC registers are unlikely to provide any useful information regarding victim location, as they relate to airflow rather than directly indicating a person's presence. The sound of movement stands out as a practical approach to rescue, enabling faster identification of where a victim may be, thus enhancing the overall effectiveness of the rescue operation in a reduced visibility scenario.