Which of the following best describes indicated altitude?

Indicated altitude best refers to the altitude as read directly from the altimeter. This is the basic reading that the pilot observes without any adjustments for atmospheric pressure or temperature. The altimeter shows the height based on the current barometric pressure setting, which can fluctuate with changes in weather conditions.

For context, altitude adjusted for temperature and pressure refers to calibrated altitude, which takes into account actual atmospheric conditions and provides a more accurate reading compared to indicated altitude. The height relative to the aircraft's takeoff point is more accurately described as the departure airport elevation rather than indicated altitude. Lastly, height measured using radar technology pertains to radar altitude, which is an entirely different measurement system that relies on radar signals and does not relate to indicated altitude readings.