Air bladder in bony fishes helps in

Options

A. buoyancy
B. food collection
C. excertion
D. digestion

Answer

### Step-by-Step Solution:

1. **Understanding the Air Bladder**: The air bladder, also known as the swim bladder or gas bladder, is an internal organ found in bony fishes. It is filled with gas.

2. **Function of the Air Bladder**: The primary function of the air bladder is to help bony fishes control their buoyancy. Buoyancy is the ability of an object to float in a fluid, which is crucial for fish as it allows them to maintain their position in the water column without expending much energy.

3. **Importance of Buoyancy Control**: By adjusting the amount of gas in the air bladder, fish can rise or sink in the water. This adaptation is particularly important in environments with varying water currents and depths, as it helps fish navigate and conserve energy while swimming.

4. **Conclusion**: Therefore, the air bladder in bony fishes primarily helps in controlling buoyancy.