Do not issue ___ instructions dependent upon the movement of arrival aircraft on the runway.

• A. Hold
• B. Taxi
• C. Conditional
• D. Proceed

Answer: (C)

The situation tests avoiding instructions that depend on a future event. A conditional instruction is one that only takes effect if something specific happens later—like an arrival aircraft moving onto the runway. In a runway environment, conditions can change quickly and unpredictably, so tying a clearance to that movement creates ambiguity and potential safety conflicts if the condition isn’t met or changes.

Instead, use clear, unconditional commands or actions tied to known, fixed points, so there’s no guesswork about whether the instruction will apply. The other terms describe concrete actions that can be carried out immediately and without waiting for another aircraft’s future movement, which is why they’re appropriate.