Question

what process led to water vapor in the atmosphere *
volcanic outgassing
photosystheisis
the water cycle
the oxygen cycle
scientists believe water was brought to early earth with *
collisions with multiple suns
collisions with other planets that already had water
collisions with asteroids, comets and meteors
earths collision with thea

Explanation:

For the first question, volcanic outgassing releases water - vapor among other gases into the atmosphere. Photosynthesis is mainly about the production of oxygen and organic compounds using light energy. The water - cycle describes the continuous movement of water on, above and below the surface of the Earth, but it doesn't explain the initial source of water vapor in the atmosphere as directly as volcanic outgassing. The oxygen - cycle is related to the movement of oxygen in different forms in the environment.
For the second question, scientists believe water was brought to early Earth by collisions with asteroids, comets and meteors which are thought to have contained water ice. Collisions with multiple suns is not a valid scientific theory for bringing water to Earth. Collisions with other planets that already had water is not the most widely - accepted theory. The Earth - Thea collision is mainly related to the formation of the Moon, not the delivery of water to Earth.

Answer:

1. volcanic outgassing
2. collisions with asteroids, comets and meteors