Answer:
A, the sun.
Explanation:
The sun powers the water cycle and many others.
The problem is that mold was growing in some of the dishes. The hypothesis is that the mold can cure bacteria.
The state of maintaining a stable internal environment regardless of changing external conditions is called 
.
The answer is seasonal changes.
<span>Animals that live in taiga biomes had to adapt to seasonal changes, by changing
their fur or feather color. For example, snowshoe rabbit and arctic fox live in
taiga and their fur color changes with environmental conditions.
To effectively camouflage, their fur is white during the winter. That
helps them blend into the snow. In the summer, where there is no snow, their
fur is brown and similar to the soil color. This way they evade predators because it is more
difficult for their predators to spot them.</span>
