Previous Year Question

The correct answer is (c) Universe.

The Big Bang Theory provides a scientific explanation for the origin and early evolution of the universe. According to it, about 13.8 billion years ago, the universe was in an extremely hot and dense state, after which space began to expand rapidly. As the universe expanded, its temperature and density gradually decreased.

As the early universe cooled, subatomic particles and then nuclei consisting mainly of hydrogen and helium were formed. About 380,000 years later, the temperature had fallen enough for electrons to combine with nuclei to form neutral atoms, allowing radiation to travel freely. This early radiation is observed today as the Cosmic Microwave Background (CMB).

The continuing expansion of the universe, CMB radiation, and the observed abundance of light elements such as hydrogen and helium are major observational supports for the Big Bang model. Later, gravitational aggregation of matter led to the formation of stars and galaxies.

Therefore, the Big Bang Theory explains not the origin of mammals, the Ice Age or oceans, but the origin and evolution of the universe.