Answer
$B$
Work Step by Step
We're raising fractions to a power, and then raising this value to a power. When raising a power to a power, we keep the base and multiply the powers. This goes for the numerator as well as the denominator. Let's rewrite the problems to reflect this:
$a^{(2/3)(2)}b^{(3/4)(2)}$
Multiply the exponents:
$a^{4/3}b^{6/4}$
Reduce fractions in the exponent by dividing numerator and denominator by their greatest common factor:
$a^{4/3}b^{3/2}$
This answer corresponds to option $B$.
