C.The grasa population would decrease.The snake and hawks population would increase..
        
             
        
        
        
Answer:The immune system protects your child's body from outside invaders, such as bacteria, viruses, fungi, and toxins (chemicals produced by microbes). It is made up of different organs, cells, and proteins that work together.
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It can work against some viruses or bacteria by sweating out the invaders.
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The most important reason for learning about environmental systems is due to the fact that we should know what's going on in the world around us. If we were to travel to Asia, we should know the forests that lie there to pack appropriately. It's also important to just be aware of how the world works. It's also good to know what rock type you'll be walking on, so you can pack shoes accordingly. Overall, it's better to know the world around you than to live in ignorance.