The region of the ionosphere where radiated power is not refracted
The region where radiated power dissipates over a specified time period
The region where radiated field strengths are constant
The region where the shape of the radiation pattern no longer varies with distance✓Correct answer
Explanation
Close to an antenna, reactive energy stored in the surrounding fields dominates and the apparent pattern changes as the measuring point moves. Far enough away that stored energy no longer matters, the pattern shape becomes fixed and only the absolute field strength falls off with distance; that region is the far field.