Which of the following safety checks should be performed on tanks before a dive?

Verifying proper pressure and checking for leaks is a critical safety check that must be performed on tanks before a dive. This step ensures that the tanks are functioning correctly and safely. Proper pressure levels indicate that the tank is adequately filled for the dive, ensuring that divers have enough air supply throughout their underwater activities. Checking for leaks is equally important; any leaks can lead to a dangerous situation where the air supply is compromised, potentially putting divers at risk.

While the other safety checks mentioned are also important in dive preparation—such as testing buoyancy compensation, examining dive suits for wear, and inspecting fins and masks—they pertain to different aspects of dive safety and readiness. Proper tank pressure and an absence of leaks are foundational to ensuring that the diving experience starts with an adequate and safe air supply, making it the most critical safety check before commencing a dive.