Final answer:
The correct transponder code for IFR in low level airspace is not given in the options; codes 1200, 7500, and 7700 have specific uses, and 2200 is not a standard code. The IFR code is usually assigned by ATC.
Step-by-step explanation:
The question concerns the correct IFR transponder code that an aircraft should set while flying under Instrument Flight Rules (IFR) in low level airspace. The options provided are A) 1200, B) 7500, C) 7700, D) 2200. The correct IFR transponder code for use in low level airspace when not in contact with air traffic control and not otherwise instructed by ATC is none of the above. These codes have specific meanings: 1200 for VFR (Visual Flight Rules), 7500 for hijacking, 7700 for general emergencies, and 2200 is not a standard transponder code in use. For IFR flight, the transponder code is typically provided by air traffic control.
The correct IFR transponder code in low level airspace is 1200. This code is used by VFR aircraft operating without an IFR clearance in airspace where communication with ATC is not required. It enables ATC to identify the aircraft on radar and provide traffic separation.The other transponder codes listed are used for different purposes. Code 7500 is for hijacking or unlawful interference, code 7700 is for an emergency situation, and code 2200 is for military aircraft.