How should an altitude of '300' feet be communicated verbally to air traffic control?

In aviation communication, clarity and standardization are paramount to ensure that all parties understand instructions or information without ambiguity. When conveying altitude to air traffic control, the use of precise and commonly recognized terms is essential.

Saying "three hundred" is the correct way to communicate an altitude of 300 feet because it follows the standard phraseology that pilots and air traffic controllers are trained to use. This format avoids any potential confusion that could arise from additional words or less formal terms. In this context, omitting "feet" makes the communication quicker and aligns with the accepted conventions of air traffic communication, where the context of altitude is implied.

The other options contain elements that may introduce ambiguity or do not meet the standard communication protocols used in aviation. For instance, including "feet" may not be necessary in casual communication with air traffic control, as the context is already understood. Terms like "three hundo" or "three cloud" are informal and could lead to misunderstandings, which is particularly critical in an environment where precision is required to ensure flight safety.