Final answer:
The present day atmosphere of terrestrial planets is largely the result of volcanic activity and impacts from asteroids and comets.
Step-by-step explanation:
The present day atmosphere of terrestrial planets is largely the result of volcanic activity and impacts from asteroids and comets.
Volcanic activity on terrestrial planets, such as Earth, Venus, and Mars, releases gases and particles into the atmosphere. Impacts from asteroids and comets also release gases and contribute to the composition of the atmospheres. These processes have shaped the current atmospheres of the terrestrial planets.