<span>1. Kuiper Belt object is made of frozen is made of frozen gas, ice, and dust that orbits in the outermost reaches of the solar system. Kuiper belt is a region which is filled with icy gaz bodies. Its structure is almost the same as the asteroid belt between Mars and Jupiter. Pluto, Makemake, Haumea are the officially recognized planets which are located in this region.
2. In my opinion, the most suitable option is: 3) The planets formed at the center of a collapsing spinning cloud of gas and dust. According to theory of solar system formation, the solar system appeared after a supernova (star explosion). A cloud of gas and dust was collapsed, and it caused a formation of a solar nebula.
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