Final answer:
IAS (Indicated Airspeed) is the airspeed read directly from an aircraft's airspeed indicator without any corrections. It is a raw reading subject to potential instrument and position errors, as well as compressibility effects at high speeds that must be corrected for more accurate readings.
Step-by-step explanation:
The student has asked what IAS (Indicated Airspeed) is corrected for. IAS is the airspeed read directly from the airspeed indicator of an aircraft without any corrections. It is the speed of the aircraft through the air, which is indicated by the aircraft's pitot-static system before any adjustments for instrument errors, position errors (due to imperfect aerodynamic airflow around the aircraft), or compressibility effects that can arise at high speed. Therefore, the correct answer to the question is that Indicated Airspeed is corrected for nothing; it is a raw reading and can be subject to various errors that need to be corrected to get true airspeed (TAS) or calibrated airspeed (CAS).