I think it is C because i got this same exact question in my class
These pockets contain the active site, which is the area of an enzyme where the substrate binds and the chemical reaction takes place. In the active site, amino acids of the enzyme protein will bind to the substrate. ... When binding to a substrate, enzymes may undergo an induced fit.
If the inner lining of the air sacs neither thin nor highly vascularized, then it can be inferred that AIR SACS ARE CANNOT BE THE SITES OF GASEOUS EXCHANGE BETWEEN AIR AND BLOOD. Air sacs are generally lined with mucus and surrounded with blood capillaries.
In case of birds, air sacs play an important role in respiratory system.
Alternative ways of representing nucleic acid chains, in this case a single strand of DNA containing only three bases: cytosine (C), adenine (A), and guanine (G). ... This structural difference is critical to the different functions of the two types of nucleic acids.
I think your answer is a hot summer. during this phase, there would be rapid growth in vegetation leading to increased population in rabbits and other rodents...