What tool saves L.B. Jefferies from harm in Rear Window?

In Alfred Hitchcock's film "Rear Window," L.B. Jefferies is initially confined to his apartment due to a broken leg. As he observes his neighbors through his binoculars, he becomes embroiled in a mystery concerning a potential murder. The critical moment when Jefferies saves himself from harm occurs when he uses his camera flashbulb.

The flashbulb serves as a crucial tool because it distracts the antagonist, allowing Jefferies a moment to escape. This use of the flash highlights both Jefferies's ingenuity and the significant role that tools from his profession play in the narrative. It symbolizes the blend of his observational skills as a photographer and the necessity of quick thinking in a dangerous situation. The flash also sheds light on the uncertainty and darkness of modern life that Hitchcock often explores—illuminating truth amid suspicion and danger.

While other options like his wheelchair or binoculars are elements that contribute to his condition or observation, they do not directly assist in saving him. His phone could connect him to others, but it doesn’t play a crucial role in the climax of the film. Thus, the camera flashbulb is the key element that transforms an act of observation into a moment of survival.