Answer:
D
Step-by-step explanation:
Using the rule of exponents
[tex]\frac{a^{n} }{a^{m} }[/tex] = [tex]\frac{1}{a^{(m-n)} }[/tex]
Given
[tex]\frac{25a^{-5}b^{-8} }{5a^{4}b }[/tex]
= [tex]\frac{25}{5}[/tex] × [tex]\frac{a^{-5} }{a^{4} }[/tex] × [tex]\frac{b^{-8} }{b^{1} }[/tex]
= 5 × [tex]\frac{1}{a^{(4-(-5))} }[/tex] × [tex]\frac{1}{b^{(1-(-8))} }[/tex]
= 5 × [tex]\frac{1}{a^{9} }[/tex] × [tex]\frac{1}{b^{9} }[/tex]
= [tex]\frac{5}{a^{9}b^{9} }[/tex] → D