Did the water on Earth come from comets?

Did the water on Earth come from comets?

Many scientists today believe that comet strikes during the early history of the solar system had positive as well as negative effects. Comet strikes may have been destructive, but it is also possible that they brought water to the Earth, and possibly even complex carbon molecules as well. The simultaneous arrival of these ingredients from outer space would help to explain the surprisingly rapid emergence of life on Earth.