The celebration of various festivals in India demonstrates:

This question tests a student's ability to identify the central idea of the passage from a set of closely worded options. The correct answer is (D) diversity, because the passage explicitly describes how the celebration of festivals like Diwali, Eid, Christmas, and regional harvest festivals showcases India's cultural variety. Option (A) 'expertise' is a distractor that has no connection to the theme of festivals and cultural identity. Option (B) 'skills' similarly misses the cultural context entirely. Option (C) 'regionalism' is the most tempting wrong answer because festivals are indeed region-specific, but regionalism carries a negative connotation of narrow regional loyalty, which contradicts the passage's message of national unity through variety. The passage frames festival celebrations as evidence of harmonious coexistence, not regional division. For exam preparation, students should note that CBSE reading comprehension questions often test whether students can distinguish between superficially similar concepts. The key strategy is to identify the tone of the passage: here it is celebratory and unifying, which aligns with 'diversity' rather than 'regionalism'. This type of question frequently appears in Section A and carries 1 mark, so spending more than 1-2 minutes on it is inadvisable. A useful tip is to eliminate clearly irrelevant options first (expertise, skills) and then carefully weigh the remaining two against the passage's overall message.