Please help this sat math problem got me stumped

Answer:
option A
Step-by-step explanation:
[tex]3x-y=12\\ =>3x = 12+y\\=>x=\frac{y+12}{3}[/tex]
Putting the value of x in [tex]\frac{8^{x} }{2^{y} }[/tex] gives :-
[tex]\frac{8^\frac{y+12}{3} }{2^y} = \frac{2^3(\frac{y+12}{3} )}{2^y} = \frac{2^{y+12} }{2^y} = 2^{y+12-y}=2^{12}[/tex]