They need sleep for energy for the day.
people need sleep to have better memory. if we dont get enough sleep, we would not be able to do tasks that need psychical energy.
its the same thing with animals: they might not have that much energy to do stuff if they dont get enough sleep.
Cold dry air sinks below the warm wet air and it pushed upwards
Letter (A.)
One result of weathering of rocks is the formation of soils.
Since weathering of rocks breaks down the surface of rocks, it affects the ground beneath them. This in turn results in formation of various kinds of soils, so I'd say B is the correct answer.
Answer: Chlorophyll is a green pigment found in plants. Plants use chlorophyll and light to make food.
