For the change in the behaviour of the children, the most effective method is:

Concept: Educational psychology recognises four broad ways to bring about a change in a child's behaviour — affectionate/persuasive guidance, reward (positive reinforcement), punishment, and social exclusion (such as expulsion). Child-centred pedagogy holds that behaviour change achieved through affectionate, reasoned guidance is the most durable, because it helps the child understand WHY a behaviour is undesirable, so the change is self-motivated rather than dependent on an external incentive or the fear of a consequence.

Application: Applying this to the four offered methods — affectionate advice explains the reason behind the desired behaviour and works through the child's own understanding and trust in the adult; the other three methods rely on an external lever (an incentive, an unpleasant consequence, or removal from the home) rather than on the child grasping why the change matters.

Cross-check — contrasting each option by its own mechanism:

• Affectionate advice: builds the child's own understanding of the behaviour, so the change tends to hold even without ongoing supervision.

• Reward: works through positive reinforcement, but the behaviour is linked to the incentive, so it can lapse once the reward stops.

• Punishment: suppresses the behaviour through the child's wish to avoid an unpleasant consequence, without addressing why the behaviour occurred.

• Expulsion from house: an extreme exclusionary measure that removes the child from the household without any explanation or guidance at all.

Result: Because it is the only option that builds lasting, self-motivated understanding rather than relying on an external incentive or a punitive lever, affectionate advice is regarded as the most effective method for changing a child's behaviour.