Answer:
A)
The Big Bang is the earliest known event in the observable Universe, its earliest known phase of evolution, and the name of the model for this process. According to this scenario, the Big Bang took place around 13.800 million years ago, when the known Universe emerged from very dense and hot matter. This theory is based on observations showing that space is expanding from an initial state where all the matter in the universe had a very high density and temperature, to a more cold and stable one.
B)
A. Closed. The universe will stop expanding and then collapse back to its point of origin.
B. Flat. The universe will stop expanding but will not collapse.
C. Open. The universe will continue to expand forever.