Are you asking the question about life on Earth, or life in general in the universe?
If it is the former, the answer could be either, with a somewhat smaller chance of life starting elsewhere in the solar system and migrating here. Mars is the most likely candidate.
Lithopanspermia between stars in a cluster is also a very small possibility.
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If it is about life in the universe as a whole, then all life started originally by abiogenesis, whether or not it has been subsequently transported by lithopanspemia or translocation by intelligent species.
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