According to the Big Bang Theory, when did creation begin?

The Big Bang Theory posits that the universe began its expansion and creation approximately 13.8 billion years ago. This timeframe is supported by extensive cosmological observations, including the cosmic microwave background radiation and the distribution of galaxies. The figure of 13 billion years is an approximation that has been refined through various scientific measurements and is widely accepted in the scientific community. Therefore, selecting the answer that indicates 13 billion years ago aligns with current astronomical evidence regarding the age of the universe as inferred from the Big Bang Theory.