Simplify the expression. Express the answer so that all exponents are positive. Whenever an exponent is 0 or negative, we assume that the base is not 0. (-5x⁴)⁻¹

The final value for the coefficient is [5 or -5] and is located in the [numerator or denominator]. The final value for the exponent for variable x is [4, -4, 5, or -5] and is located in the denominator. If there is no value to place in the numerator or denominator, a [x, 0, or 1] is inserted to hold the place value.

a. 1 / (5x⁴)
b. 1 / 5
c. 5 / (x⁴)
d. 1 / (-5x⁴)