Answer:
B
Step-by-step explanation:
using the rule of exponents
[tex]a^{m}[/tex] × [tex]a^{n}[/tex] = [tex]a^{(m+n)}[/tex] , then
[tex]8^{5}[/tex] × [tex]8^{4}[/tex] = [tex]8^{(5+4)}[/tex] = [tex]8^{9}[/tex]
