It depends on your teacher, it should be A. It could be B if that’s what your teacher wants but I would go with A.
It would be making soda I'm pretty sure
It contributes to global warming by wastage of food produces carbon dioxide which releases more green house gases so the more wastage the more carbon dioxide being released.
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Not sure what you mean but here's what i think
1.They are substrate-specific, because it's a lock-and-key mechanism.
2. They are re-used
3. They can catalyze reactions
4. They decrease activation energy
5. They are proteins by nature.