The correct option is (c).
Explanation
Stars are massive, luminous spheres of plasma held together by their own gravity. They are fundamental celestial bodies characterized by their immense size, high temperatures, and ability to generate energy.Statement-wise Analysis:
- Statement 1 is Incorrect: Stars are typically very large and extremely hot bodies. While they vary in size (from dwarfs to supergiants), they are generally massive compared to planets. They are not cold; their surface temperatures range from thousands to tens of thousands of degrees Celsius, and their cores reach millions of degrees.
- Statement 2 is Correct: Stars are composed primarily of gases, specifically hydrogen and helium. Under the intense heat and pressure within a star, these gases exist in a state of matter known as plasma.
- Statement 3 is Correct: Stars emit their own heat and light. This energy is produced in their cores through nuclear fusion reactions, where hydrogen nuclei fuse to form helium, releasing vast amounts of energy. This distinguishes stars from planets and satellites, which do not produce their own light but reflect the light of stars.
Key Takeaway: Stars are huge, hot celestial bodies made of gases that possess the unique ability to emit their own heat and light due to internal nuclear fusion.