The trees such as _______ produced most of the oxygen in the atmosphere.

The pines are a group of approximately 250 woody, seed-producing plants. Conifers such as cedars, spruces, firs, and pines are among them. Pines have one of the most widespread distributions of any conifer, despite being found almost entirely in the Northern Hemisphere.

Plants produce oxygen by a process called photosynthesis.

An oak is a tree or shrub in the beech family, Fagaceae, genus Quercus. There are approximately 500 species of oaks left on the planet.

A stand or group of aspen trees is thought to be a single organism, with the main life force located underground in the extensive root system. Before a single aspen trunk appears above the surface, the root system may be dormant for many years, waiting for the right conditions, including enough sunlight.

Oxygen is produced by phytoplankton and green plants.

Most of the oxygen produced in the atmosphere are maple,spruce,oak,aspen,and pines.