Homeostasis is the process by which organisms keep internal conditions relatively constant<span> despite changes in external environments. Homeostasis in the body is maintained by feedback loops.
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Answer:
1. Precambrian rocks are very old.
2. They have very few fossils.
As we know, vaccines contain weakened or inactive parts of a particular organism (antigen) that triggers an immune response within the body, which is a training for your body so if a real antigen attacks it, it will be trained and kill it with ease. Same thing with the boxer, he is training with dead weight so when he has a boxing match he will be ready and win with ease.
The answer to your question is going to be is B
