UPSC Prelims 2013Science & TechnologyQuestion 3 of 16Consider the following phenomena: 1. Size of the sun at dusk 2. Colour of the sun at dawn 3. Moon being visible at dawn 4. The twinkle of stars in the sky 5. Polestar being visible in the sky Which of the above are optical illusions?A1, 2 and 3B3, 4 and 5C1, 2 and 4D2, 3 and 5See explanation
