The answer is C
The more plants there are, the more consumers there are. If there aren't enough plants, the consumers have no way of getting energy, and therefore cannot survive. The species also matters, because certain species of plants can only be eaten by certain species of consumers.
Plants may wilt because the soil is dry and the plants don't have enough to water to survive. If you add shade, this means that the sun no longer shines down directly on the soil, helping the soil stay damp. Less water evaporates from the soil, and the plants don't wilt as much.
A seed of a flowering plant or gymnosperm may contain tissues from three generations. Similar to gymnosperms, angiosperms also are seed producing plants, but are distinguished from gymnosperms by features such as flowers, endosperm within the seeds, and the production of fruits that contain the seeds.
