Bees use pheromones to communicate about what kind of threats?

Bees utilize pheromones as a sophisticated form of chemical communication, particularly when it comes to indicating threats such as predators or intruders. When a bee detects a potential danger, it can release alarm pheromones to alert other members of the colony. These pheromones signal the presence of threats, prompting the bees to take defensive actions, such as forming a protective cluster or attacking the intruder. This form of communication is crucial for the survival of the colony, as it ensures that all bees are aware of the potential danger and can respond accordingly.

In contrast, the other options relate to different aspects of the bees' environment that do not involve immediate threats. While bees do communicate about food sources, pollen availability, and water, these typically involve different pheromones or behaviors, such as foraging signals and recruitment dances, rather than the alarm pheromones used to notify about predators or intruders.