Evaluate the following indefinite integral.
(∫ (6x⁵ - 5/x⁵) , dx)
a) (x⁶ + 5/x⁴ + C)
b) (x⁶ - 5/4x⁴ + C)
c) (x⁶ - 5/6x⁶ + C)
d) (x⁶ + 5/6x⁶ + C)