Which of these processes did NOT contribute to Mars losing its atmosphere about two billion years ago?

Question

Quizplus · Accepted Answer

The greenhouse effect did not contribute to Mars losing its atmosphere. The primary factors were stripping by the solar wind, breakup of molecules by solar ultraviolet radiation, and some gases freezing and being buried under the surface. The greenhouse effect is a process that warms a planet's surface, not one that leads to atmospheric loss.

Which of These Processes Did NOT Contribute to Mars Losing