Question

Where do supporters of the outside-in model say Earth’s water originated from?

Inside of volcanoes
Inside the atmosphere
Bonded to meteorites that hit the Earth
Bonded to minerals in Earth's mantle

Answer 1

They believed that Earths water originated from extraterrestrial sources such as comets which brought water to the planet.

Answer 2

Bonded to meteorites that hit the Earth

Step-by-step explanation:

Some hypothesis refering to origin of water on Earth sugges, that a very long time ago as asolar system was young, some asteroids may have landed also carrying frozen water. The meteorites would then turn to provide liquid water, these meteorites were protoplanets from the outer asteroid belt that is in the solar system.

However this still is not the mainstream theory.