When observing bubbles at the surface while scuba diving, what can divers determine?

When divers observe bubbles at the surface while scuba diving, they can determine their location underwater. The presence of bubbles indicates that air is escaping from the divers' equipment, which travels upwards due to buoyancy. By observing the direction and movement of the bubbles, divers can get a sense of their orientation and position relative to the surface. If the bubbles are rising directly above them, for instance, it suggests that they are directly below that point on the surface.

The other options relate to factors that cannot be accurately gauged solely by observing bubbles at the surface. Depth cannot be determined just by bubbles; divers require a depth gauge for precise measurements. Similarly, air supply and water temperature assessments rely on other equipment or indicators, like pressure gauges and thermometers, rather than bubble observation. Thus, the ability to use bubbles for locating oneself underwater is crucial for safe navigation and orientation during a dive.