The equivalent expression is b⁴/a. Option A
To determine the equivalent expression, we have to know that index forms are mathematical models used to represent numbers or variables that are too large or too small in more convenient forms.
Then, we have that;
a³b⁵/a⁴b
Now, to simply the expression, we have to subtract the exponential value of the divisors with same bases, we then have;
a³⁻⁴b⁵⁻¹
subtract the values, we get;
a⁻¹b⁴
This is also expressed as;
b⁴/a