Concept:Understanding Jerome Bruner's principles for effective classroom teaching.Explanation:Jerome Bruner, a renowned psychologist, proposed several key principles for effective teaching and learning, particularly within his "Discovery Learning" framework. He emphasized that for a classroom to be truly effective, several elements must be in place alongside the learner's readiness and the way content is structured (content construction) and sequenced (instructional order).Bruner's theory highlights that learners are active participants, and providing timely reinforcement is crucial. This reinforcement helps solidify understanding and motivates learners to progress towards their goals. It's like giving a pat on the back when a student grasps a difficult concept, encouraging them to continue learning.While attention and retention are vital cognitive processes in learning, Bruner specifically identified reinforcement as a critical pedagogical element that complements readiness, content construction, and instructional order for effective teaching.Answer:A. Reinforcement