Concept:Bloom's Taxonomy categorizes cognitive skills. The "Application" level means using learned concepts in new, real-life situations.Explanation:Question B asks how democratic principles are used in family management. This requires applying a concept to a personal context.Question D asks how democratic principles can be used in school activities. This also demands applying the idea to a new setting.Question E involves calculating sex-ratio from given population data. This uses the formula in a practical computation.These three questions test the ability to apply knowledge. Question A asks for a definition and a book name – that is recall. Question C asks for a description – that is understanding.Answer:B, D and E (Option D)