Answer:
I choose A, it seems loke the best choice
Explanation:
The correct answers are under predation and under rainfall.
The reason for migration can be rainfall,
because some herbivores follow the rain to new sources of water and grass. Also, predators migrate because they follow some animal migrants that are used for food, so predation is one of the reasons that lead to migration.
In polysaccharides, there are multiple bond present as they are made up of many monosaccharides and oligosaccharides .
but for monosaccharides , there is no barrier of multiple bonds breakage thus easily digestible !