It is d. If it was adaptation, the organism would have stayed in order to adapt. The species moved in order to not go extinct. It can not be speciation, because a new species was not made. It is stimulus. It experienced too much heat, so it left.
The HCG hormone is the answer possibly
A. There are 4 codons
Idk B
the is a definite article meaning that you cannot use it
"an" can only be used before words beginning with vowels
therefore the answer is" a"
