Blocking of behaviour that is directed towards a goal is ______.

Concept: In psychology, frustration is the specific emotional state that arises when a person's goal-directed behaviour is blocked, obstructed, or otherwise prevented from reaching its target. It names interference with a goal in progress, not any behaviour that may follow such interference.

Application: The stem describes exactly this situation — behaviour aimed at a goal being blocked. That is the standard definition of frustration used in educational psychology, so the term that completes the blank is frustration.

Cross-check: Each of the other terms describes a different concept and does not fit the stem's description of blocking:

• Emotion is a broad affective state (such as joy, anger, or fear) and is not specific to the obstruction of a goal, so it is too general to match the stem.

• Motivation is the drive that initiates and sustains movement toward a goal — it energises behaviour rather than blocking it, which is the opposite of what the stem describes.

• Aggression is a behavioural reaction that can sometimes follow an obstacle, but it names a possible response to interference, not the act of blocking itself.

Since the stem is the textbook definition of interference with goal-directed behaviour, the fitting term is frustration.