Which process describes the seeding of life on Earth from outer space?

Panspermia is the process that describes the idea that life, or the building blocks of life, may have originated from outer space and been seeded onto Earth through meteorites, comets, or other celestial bodies. This hypothesis suggests that life did not necessarily originate on Earth itself but may have been distributed throughout the universe, ultimately allowing it to flourish in suitable environments like our planet.

This concept supports the idea that microorganisms or organic molecules could survive the harsh conditions of space and, upon reaching Earth, could contribute to the origins of life here. This distinguishes it from other biological processes mentioned in the options.

Endosymbiosis refers to the process by which certain organelles, like mitochondria and chloroplasts, evolved through a symbiotic relationship between different species. Allopatric isolation pertains to the geographic separation of populations, leading to speciation. Speciation itself describes the process by which new species arise, typically through evolutionary mechanisms like natural selection and genetic drift. These processes are essential to the understanding of life's diversity and evolution but do not directly address the origin of life from extraterrestrial sources.