Which shows the following expression after the negative exponents have been eliminated?

Answer:
[tex]\frac{a^3b^4}{ab^2}[/tex] which is the last choice in the question
Step-by-step explanation:
Simplify
[tex]\frac{a^3b^{-2}}{ab^{-4}} = \frac{a^3}{a}\frac{b^{-2}}{b^{-4}}[/tex]
Using the fact that [tex]\frac{x^m}{x^n} =x^{m-n}[/tex]
We get
[tex]\frac{a^3}{a} = a^{3-1} = a^2[/tex]
[tex]\frac{b^{-2}}{b^{-4}} = b^{-2-(-4)} = b^2[/tex]
So
[tex]\frac{a^3b^{-2}}{ab^{-4}} =a^2b^2[/tex]
Multiplying numerator and denominator by [tex]ab^2[/tex] gives
[tex]a^2b^2 \frac{ab^2}{ab^2}[/tex]
= [tex]\frac{a^3b^4}{ab^2}[/tex] ANSWER
Hint:
We can eliminate first choice since negative exponents still remain
We can eliminate third choice because the expression has a minus sign which is not possible
That just leaves second and fourth choices to work with