What percentage of Venus's atmosphere is made up of carbon dioxide?

The correct answer, which indicates that approximately 96% of Venus's atmosphere is composed of carbon dioxide, reflects the planet's unique atmospheric composition. This high concentration of carbon dioxide contributes to a substantial greenhouse effect, making Venus the hottest planet in the solar system despite its distance from the Sun.

Understanding this percentage highlights the stark difference between Venus and Earth in their atmospheric makeups. While Earth possesses a mixture of gases, including nitrogen, oxygen, and trace amounts of carbon dioxide, Venus's thick CO2 atmosphere prevents heat from escaping, leading to extreme surface temperatures. This is a crucial factor in studying planetary atmospheres and climate dynamics.

The other options propose lower percentages that do not accurately reflect current scientific data regarding Venus's atmosphere. By solidifying the understanding of Venus's atmospheric composition, the information becomes vital for comparisons in planetary science and for grasping the fundamental mechanisms of climate and temperature on different planets.