I think it is A but I am not completely sure
They just told me to answer a bunch of questions to get points best of luck tho!
Store Carbon and exchange for oxygen
<span>It means that they only act on certain types of substrates. Each enzyme is </span><span>specific in that they do not work for all molecules.</span>
Rubies are the most valuable members of the corundum family. Large gem-quality rubies can be more valuable than comparably sized diamonds and are certainly rarer. There is a relative abundance of smaller, 1-3 carat blue sapphires compared to the scarcity of even small gem-quality rubies.