Given the labour output function for the laundry service:
\[ O = (a^0 - 4L^0)^6 \]
where \(L\) denotes labour and \(O\) denotes output.
1. \(a^0\) is always equal to 1 for any non-zero \(a\).
2. \(L^0\) is always equal to 1 for any non-zero \(L\).
Thus, the expression simplifies to:
\[ O = (1 - 4 \cdot 1)^6 \]
\[ O = (1 - 4)^6 \]
\[ O = (-3)^6 \]
\[ O = 729 \]
Therefore, the output \(O\) remains constant at 729, regardless of the amount of labour \(L\).
Correct answer is Option C : Remains constant irrespective of the amount of labor.