Which of the following is/are cited by the scientists as evidence/ evidences for the continued expansion of universe? 1. Detection of microwaves in space 2. Observation of redshift phenomenon in space 3. Movement of asteroids in space 4. Occurrence of supernova explosions in space Select the correct answer using the codes given below:

1. Statement 1 is correct. The detection of the Cosmic Microwave Background (CMB) radiation, faint microwaves filling all of space, is considered strong evidence for the Big Bang theory. The Big Bang model posits an initial hot, dense state followed by expansion and cooling, which naturally leads to the prediction of the CMB. Therefore, the CMB is fundamental evidence supporting the concept of an expanding universe originating from a hot past. 2. Statement 2 is correct. The observation of redshift in the light spectra from distant galaxies is the primary evidence for the continued expansion of the universe. This redshift indicates that these galaxies are moving away from us, and the further away they are, the faster they recede (Hubble's Law). This systematic recession is interpreted as the expansion of space itself. 3. Statement 3 is incorrect. The movement of asteroids within our solar system is governed by local gravitational forces and orbital mechanics. It does not provide evidence for the large-scale expansion of the universe. 4. Statement 4 is incorrect as primary evidence for *continued* expansion (though crucial for *accelerated* expansion). While the study of Type Ia supernova explosions as standard candles has provided crucial evidence for the *accelerated* expansion of the universe, the fundamental evidence for the expansion itself comes primarily from the redshift phenomenon. Supernova data builds upon the initial discovery of expansion via redshift. Given the options, redshift (2) is the most direct evidence for continued expansion, and CMB (1) supports the underlying model.