Which method of communication is commonly used underwater?

Hand signals are the correct choice for underwater communication because they allow divers to convey messages effectively while being submerged in an environment where sound travels poorly and is often distorted. Diving conditions, such as the presence of water and the surrounding environment, make verbal communication virtually impossible.

Hand signals enable divers to communicate critical information, such as safety issues, instructions, or observations, without the need for words. Divers often establish a common set of signals before a dive to ensure that all team members understand each other clearly.

Other forms of communication, such as light signals, can also be utilized to some extent, but they are not as universally applicable or effective as hand signals in various underwater conditions. Submersible radios may work in some situations, but they require specialized equipment and are not widely used among recreational divers.