Under which condition must the pilot in command of a civil aircraft have at least an instrument rating?

The correct answer is that the pilot in command of a civil aircraft must have at least an instrument rating for a flight in VFR conditions while on an IFR flight plan. When operating under an IFR (Instrument Flight Rules) flight plan, the expectations and requirements shift significantly. The pilot is responsible for flying according to IFR regulations, which includes instrument flight and the ability to navigate through both VFR (Visual Flight Rules) and IFR conditions.

Even if the weather conditions are VFR (meaning the weather is generally good), if the pilot is operating under an IFR flight plan, they are subject to IFR regulations, which necessitate having an instrument rating. This rating ensures that the pilot has the requisite training and skills to handle the aircraft in less than ideal flying conditions, should the weather unexpectedly change or if they enter controlled airspace or areas of restricted visibility.

In contrast, the other scenarios either do not mandate an instrument rating or have conditions that would not necessarily require it. For example, operating in Class E airspace or above 1,200 feet AGL with specified visibility may not always require an instrument rating unless specific additional conditions exist. Class B airspace also doesn’t inherently require an instrument rating unless the flight is conducted under IFR.