Concept:
Extension education is an informal, participatory, and learner-centered system focused on behavioral change and practical learning.
Step 1: Nature of Extension Education
• Non-formal education system
• Focuses on practical application
• Encourages participation and self-learning
Step 2: Evaluation of Each Statement
Statement A
• Incorrect → Extension is NOT classroom-based
Statement B
• Incorrect → Extension is participatory, not one-way
Statement C
• Incorrect → Basic unit is group/community, not individual
Statement D
• Correct → Promotes critical thinking and decision-making
Statement E
• Correct → Learning by doing is core principle
Step 3: Final Conclusion
\[
\boxed{\text{D and E only}}
\]
\[
\boxed{\text{Option (A)}}
\]