Answer : 2. "Explore"
Explanation :

The 5 E's learning model, developed by 'Rodger Bybee' is an instructional model based on 5 stages which are engaging, exploration, explanation, extend, and evaluation. This constructivist model of learning ensures the active involvement of learners in the teaching-learning process. Engagement phase: In this, students are engaged in the classroom through different learning tasks. This learning task may be an activity, showing any surprising event, peculiar examples etc, where students will get an opportunity to relate their previous knowledge with the existing ideas. Exploration Phase: In this phase, the students have an opportunity to get directly involved with the phenomena and materials. Involving themselves in these activities they develop a grounding of experiences with the phenomenon. Explanation Phase: The third stage is the point at which the learner begins to put the abstract experience and clarify their misconception through discussion in the classroom. You will explain the concept only after students have got the common experiences through collaboration. Elaboration Phase: This phase of this learning cycle provides an opportunity for students to apply their knowledge to new situations, which may include raising new questions and hypotheses to explore. Evaluation Phase: The fifth ‘E’, is an on-going diagnostic process that allows you to determine, whether the learner has attained an understanding of concepts and knowledge.