To what does the term 'drying a liquid' refer?

a. removing all traces of water to form a solid.
b. the technique of removing all traces of an organic solvent from water.
c. removing all traces of water from an organic solvent.
d. the extraction of a solid from a polar solvent.

a. Removing all traces of water to form a solid

Explanation:

How this model explains the causes of seasonal changes in the Northern Hemisphere is by showing the tilt and the orbit around the sun. As you see stage 3 represents summer in the Northern Hemisphere and stage 1 represents winter in the Northern Hemisphere. Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth receive the Sun's most direct rays. So, when the North Pole tilts toward the Sun, it's summer in the Northern Hemisphere. And when the South Pole tilts toward the Sun, it's winter in the Northern Hemisphere.