What are two methods used to inflate a buoyancy compensator (B.C.)?

Inflation methods for a buoyancy compensator (B.C.) are essential for achieving proper buoyancy control while diving. The correct answer highlights the common methods used: power inflation and oral inflation.

Power inflation refers to using a compressed air source connected to the B.C., often found in dive shops or self-inflating devices. This method allows divers to quickly and efficiently add air to their buoyancy compensator, which is particularly useful when descending or maneuvering through various water conditions.

Oral inflation is a manual method in which divers use their breath to fill the B.C. This is useful in situations where a power source is not available or when making fine adjustments to buoyancy. It ensures that divers maintain complete control over their buoyancy at all times.

The other options mention methods that are either less common or not standard for inflating a B.C. For instance, hand pumps and carbon dioxide cartridges are not typical methods for buoyancy compensators and might be associated with different types of inflatables rather than standard diving gear. Understanding these methods is crucial for safe and effective diving practices.